ANKARA, Nov. 1 -- Since the expulsion of the Islamic State (IS) from its Syrian and Iraqi headquarters, hundreds of foreign fighters have reportedly returned home including Turkey, likely to be one of their future targets, despite intense counterterrorism activities.

Turkish anti-terror squads have led a massive crackdown against jihadist cells across Turkey, arresting some 150 suspects last weekend.

Some of them were seemingly planning bloody attacks in Istanbul, Turkey's most populated city and economic hub, on Oct. 29, Turkey's Republic Day.

During an investigation of two residences determined to be jihadist cells where fires had broken out on Oct. 28, two plotters were identified as Austrian citizens of Turkish origin, police said in a statement.

The police also found and raided two other cells in Istanbul, which have been identified to have been in the Arnavutkoy district on the European side of Istanbul for the past five years.

The news came after Istanbul police foiled a major planned IS bomb attack and brought down two very significant jihadist cells in the city one day prior to the Republic Day celebrations.

According to police, a car loaded with explosives and a bomb-laden motorcycle were found in the parking lot of a shopping mall in Istanbul's Bayrampasa district on Saturday.

"Objects used in bomb making, including chemical materials ... electronic circuits, cables, batteries and many other similar materials, were found in two houses," the police said in a written statement.

It said 66 home-made explosives with remote control set-ups, suicide vests, two firearms and many bullets were confiscated from the motorcycle and the car.

"It seems that the arrested suspects were planning a massacre during Republic Day. The police did a wonderful job otherwise a lot of blood would have been spilled again," said security analyst Abdullah Agar during an interview to the 24 TV channel.

"Such attacks aim to divide the society where it is planned, to create havoc, chaos and a state of panic among the population," indicated Agar, warning that there is still many risks from IS towards Turkey, and Turks should be very careful.

In a series of new details about this major crackdown, the police told the Anadolu Agency that the arrested suspects were planning no less than four suicide attacks in Istanbul on the same day, aiming to kill dozens of civilians who were chanting and demonstrating in the streets of the metropolis.

According to sources quoted by Anadolu Agency and the local press, the jihadists also planned to attack a shopping mall to carry out a massacre with suicide vests.

Thousands of foreign IS supporters have returned to their home countries after leaving Syria and Iraq over the past two years, especially last weeks.

Last week, the New York-based Soufan Center, an American NGO dealing with security matters, published a report, saying that at least 5,600 people from 33 countries left IS-held areas since two years, with the number increasing as the group began to suffer territorial losses. Some 900 of them have returned to Turkey, according to this report.

More than 40,000 foreigners from 100 different countries joined the jihadist movement after it declared the establishment of a "caliphate" in 2024 after seizing large portions of land in Syria and Iraq.

The group's self-proclaimed capital in Syria, Raqqa, fell to the U.S.-backed Syrian Democratic Forces (SDF) in early October, and in June Iraqi forces liberated Mosul from IS fighters, one of Iraq's biggest cities.

After a series of deadly attacks that rocked big cities such as Ankara and Istanbul in the past two years, Turkey, accused by some in the past of turning a blind eye to IS, is waging a full fledged war against the terrorist group.

According to the Turkish authorities, more than 5,000 suspected IS militants have been arrested and some 3,300 foreign fighters have been deported since January 2024.

But the authorities also fear that despite more effective border control (Syria and Iraq) where huge walls have been erected with constant police repression in major cities, there could be an increase of attacks on Turkish soil in order to make up for the damage suffered in Raqqa and Mosul.

"We see that foreign fighters are returning home and Turkey, as a country where militants are coming back to, is surely under threat," told Xinhua Can Acun, a Middle East expert at the Ankara-based Foundation for Political, Economic and Social Research think tank.

Acun mentioned that the Turkish military has managed to sweep up jihadist forces near its borders with the Euphrates Shield operation (September 2024 to March 2024) in Syrian soil.

The expert underlined the increase of intelligence obtained by Turkish security forces since last summer that led to "the collapse in general of the Daesh cells in Turkey," adding the capacity of the extremist movement to organize significant attacks has been severely diminished.

"Of course there are still risks but compared to the past, I think that Turkey is safer now," argued Acun.

The New Year's Eve attack against a night club in Istanbul which killed 39 people was the last major incident linked to IS in Turkey. The gunman was apprehended a few weeks later and is awaiting trial.

ANKARA, Nov. 1 -- Since the expulsion of the Islamic State (IS) from its Syrian and Iraqi headquarters, hundreds of foreign fighters have reportedly returned home including Turkey, likely to be one of their future targets, despite intense counterterrorism activities.

Turkish anti-terror squads have led a massive crackdown against jihadist cells across Turkey, arresting some 150 suspects last weekend.

Some of them were seemingly planning bloody attacks in Istanbul, Turkey's most populated city and economic hub, on Oct. 29, Turkey's Republic Day.

During an investigation of two residences determined to be jihadist cells where fires had broken out on Oct. 28, two plotters were identified as Austrian citizens of Turkish origin, police said in a statement.

The police also found and raided two other cells in Istanbul, which have been identified to have been in the Arnavutkoy district on the European side of Istanbul for the past five years.

The news came after Istanbul police foiled a major planned IS bomb attack and brought down two very significant jihadist cells in the city one day prior to the Republic Day celebrations.

According to police, a car loaded with explosives and a bomb-laden motorcycle were found in the parking lot of a shopping mall in Istanbul's Bayrampasa district on Saturday.

"Objects used in bomb making, including chemical materials ... electronic circuits, cables, batteries and many other similar materials, were found in two houses," the police said in a written statement.

It said 66 home-made explosives with remote control set-ups, suicide vests, two firearms and many bullets were confiscated from the motorcycle and the car.

"It seems that the arrested suspects were planning a massacre during Republic Day. The police did a wonderful job otherwise a lot of blood would have been spilled again," said security analyst Abdullah Agar during an interview to the 24 TV channel.

"Such attacks aim to divide the society where it is planned, to create havoc, chaos and a state of panic among the population," indicated Agar, warning that there is still many risks from IS towards Turkey, and Turks should be very careful.

In a series of new details about this major crackdown, the police told the Anadolu Agency that the arrested suspects were planning no less than four suicide attacks in Istanbul on the same day, aiming to kill dozens of civilians who were chanting and demonstrating in the streets of the metropolis.

According to sources quoted by Anadolu Agency and the local press, the jihadists also planned to attack a shopping mall to carry out a massacre with suicide vests.

Thousands of foreign IS supporters have returned to their home countries after leaving Syria and Iraq over the past two years, especially last weeks.

Last week, the New York-based Soufan Center, an American NGO dealing with security matters, published a report, saying that at least 5,600 people from 33 countries left IS-held areas since two years, with the number increasing as the group began to suffer territorial losses. Some 900 of them have returned to Turkey, according to this report.

More than 40,000 foreigners from 100 different countries joined the jihadist movement after it declared the establishment of a "caliphate" in 2024 after seizing large portions of land in Syria and Iraq.

The group's self-proclaimed capital in Syria, Raqqa, fell to the U.S.-backed Syrian Democratic Forces (SDF) in early October, and in June Iraqi forces liberated Mosul from IS fighters, one of Iraq's biggest cities.

After a series of deadly attacks that rocked big cities such as Ankara and Istanbul in the past two years, Turkey, accused by some in the past of turning a blind eye to IS, is waging a full fledged war against the terrorist group.

According to the Turkish authorities, more than 5,000 suspected IS militants have been arrested and some 3,300 foreign fighters have been deported since January 2024.

But the authorities also fear that despite more effective border control (Syria and Iraq) where huge walls have been erected with constant police repression in major cities, there could be an increase of attacks on Turkish soil in order to make up for the damage suffered in Raqqa and Mosul.

"We see that foreign fighters are returning home and Turkey, as a country where militants are coming back to, is surely under threat," told Xinhua Can Acun, a Middle East expert at the Ankara-based Foundation for Political, Economic and Social Research think tank.

Acun mentioned that the Turkish military has managed to sweep up jihadist forces near its borders with the Euphrates Shield operation (September 2024 to March 2024) in Syrian soil.

The expert underlined the increase of intelligence obtained by Turkish security forces since last summer that led to "the collapse in general of the Daesh cells in Turkey," adding the capacity of the extremist movement to organize significant attacks has been severely diminished.

"Of course there are still risks but compared to the past, I think that Turkey is safer now," argued Acun.

The New Year's Eve attack against a night club in Istanbul which killed 39 people was the last major incident linked to IS in Turkey. The gunman was apprehended a few weeks later and is awaiting trial.