Amid fears that Daesh militants who fled Syria may likely hit Europe and Turkey, authorities heightened crackdowns against the terrorist group with daily operations to net suspected militants. Yesterday, 121 suspects, including Syrians and Iraqis, were captured in counterterrorism operations across the country. Though Daesh lost many strongholds in Iraq and Syria, a controversial deal between the militants and Syrian groups linked to the PKK, a major terrorist group which carries out attacks in Turkey, helped their safe evacuation in Syria. Turkey shares a lengthy border with war-torn Syria and struggles to keep it safe from infiltration through a giant border wall currently under construction.

The country is at the forefront in efforts to quell threats from the terrorist group, which partly depends on foreign recruits for manpower. Turkey has stopped thousands trying to enter Syria to join the group over the past few years. It now fights the phenomenon of militants fleeing Iraq and Syria.

Early yesterday, police raided apartment buildings in the Osmangazi, Yıldırım and İnegöl districts of Bursa, a province south of Istanbul. Special Operations police using battering rams stormed the apartments to capture the suspects. In two apartments in the same building, police nabbed 17 suspects and thoroughly searched properties while 21 others were captured in other raids.

Most suspects were Syrians, media outlets reported. In the western city of Manisa, five suspects, including Syrian nationals, were captured in two operations in the Salihli and Turgutlu districts. Another operation in the eastern city of Elazığ nabbed eight suspects. In other operations in the eastern provinces, police detained 22 suspects in Van, Diyarbakır and Mardin. Authorities in the eastern city of Bingöl also issued arrest warrants for 26 suspects. Twenty-one suspects were captured while the rest remains at large.

In Sakarya, a northwestern province, three Iraqi nationals linked to the terrorist group were nabbed. Police found $138,000 in the suspects' possession. The suspects were working as a grocer, livestock breeder and worker in the city, authorities said. Police also said they confiscated "digital material" linked to Daesh in the operations.

Six foreign suspects including one woman were arrested in Daesh operations in Istanbul's Başakşehir, Ümraniye and Güngören districts. Their nationalities were not revealed, but security sources said they were planning attacks.

In the southern city of Gaziantep, a major hub for Syrian migrants as it borders with Syria, 17 suspects linked to the terrorist group were detained. Security forces found a pistol, two rifles and a large cache of ammunition in the suspects' possession.

Media reports say hundreds of Daesh terrorists are headed toward Europe after secretly escaping war-torn Syria thanks to a deal struck between the terror group and the U.S.-backed Syrian Domestic Forces (SDF), which is mostly made up of the People's Protection Units (YPG) - the PKK's Syrian offshoot.

The deal allowed hundreds of Daesh militants to escape Raqqa during civilian evacuations, paving the way for the terrorists to enter mainland Europe via smuggling routes - a danger Turkey has warned Europe of on many occasions.

The secret deal was exposed by a BBC report which detailed the agreement between the SDF, which is predominantly composed of YPG fighters, and Daesh to arrange the escape of thousands of militants, including some of the most notorious, and their families from Raqqa, with 10 trucks loaded with weapons and ammunition on Oct. 12. The report put the number of evacuated terrorists and family members at around 4,000.

"YPG terrorists allowed Daesh to leave Raqqa with their weapons instead of eliminating them from the city. One terrorist group left Raqqa and another settled in. Is this your rational policy?" Prime Minister Binali Yıldırım said after the deal was revealed.

Turkey has been targeted by many deadly Daesh attacks since 2015. Ankara has deported more than 5,000 Daesh suspects and 3,290 foreign terrorists from 95 countries in recent years and has dismantled several terrorist cells that provided logistical assistance in Syria and Iraq and for plotting attacks inside the country.

The country's efforts against Daesh made it a primary target for the terrorist group, which has carried out numerous gun and bomb attacks targeting security forces and civilians. This includes the country's deadliest terrorist attack, which killed 102 people and wounded 400 others in a twin suicide bombing at a peace rally in Ankara on Oct. 10, 2015. Next week, Turkey will mark the first anniversary of a Daesh raid on a popular nightclub in Istanbul where 39 people, including foreigners, were killed during New Year's Eve celebrations.