A top-level security meeting chaired by President Recep Tayyip Erdoğan has been concluded in Istanbul on Sunday, following Saturday's terror attack, according to presidency sources.

The meeting started at 4:30 p.m. local time (1330GMT), with Prime Minister Binali Yıldırım, Deputy Prime Ministers Numan Kurtulmuş, Veysi Kaynak and Tuğrul Türkeş. Several ministers also attended the meeting.

The meeting at the Mabeyn Presidential Pavilion lasted for two hours.

Terrorist group PKK's suicide team, known as the Kurdistan Freedom Hawks (TAK), assumed responsibility Sunday for the terrorist bomb attacks that killed 39 people and injured 155 Saturday night in Istanbul's Beşiktaş district.

Intelligence sources said on Sunday that one of the suspected suicide bombers of the deadly attack entered Turkey from the PYD-controlled area in Syria.

The People's Protection Units (YPG), which is the military wing of the PYD, had previously threatened Turkey with terror attacks with a video released in February this year where the group declared war on Turkey.

Both the PYD and the YPG are the offshoot of the PKK terrorist organization operating in Syria. The militants often receive training in Syria in YPG positions and travel to Turkey to carry out attacks for TAK or PKK, both groups share organic ties with the PYD/YPG.

TAK said that two of their members died in the attacks, but they did not specify if they were suicide attackers, adding that they will release the information of the attackers in upcoming days.