Main suspects Habib Aktas and Azad Ekinci met with bin Laden's top lieutenant, Ayman al-Zawahiri, several times, Hurriyet newspaper reported, quoting the testimony from another suspect. The two Turks are suspected of planning the Nov. 15 suicide bombings of two synagogues and of the British Consulate and a British bank five days later.
"They were the only ones to meet with al-Zawahiri," Hurriyet quoted the man, identified as Yusuf Polat, as telling police during questioning. "The instructions came from him. They would meet (with him) at least three times a year, using false identity documents."
Milliyet and Zaman newspapers carried similar reports. Police would not comment on the reports.
The reports came a day after Deputy Prime Minister Abdullatif Sener said following a Cabinet meeting that "those who were involved in these terrorist attacks as suicide bombers, and those who had relations with them ... are linked to the al Qaeda terrorist organization."
At least three claims of responsibility for the bombings purportedly came from al Qaeda. The government had been hesitant to name al Qaeda and Sener's statement was the first time the government outright linked the attacks to bin Laden's network.
The man identified as Polat was captured while trying to travel into Iran and charged over the weekend with a crime equivalent to treason — the most prominent arrest to date in the investigation. Newspapers have said he confessed to belonging to a small al Qaeda cell in Turkey.
Police said he surveyed the site for one of the synagogue bombings and gave the go-ahead for the attack.
Newspapers initially identified Ekinci as one of the suicide bombers, but he is now described as one of the ringleaders.
Police believe that he, Aktas and four other suspected ringleaders of a Turkish cell linked to al Qaeda fled abroad just before the attacks, Cumhuriyet newspaper reported.
On Sunday, Syria handed over 22 suspects in the bombing at Turkey's request. Two of the suspects — a husband and wife — were brought to Ankara for questioning by anti-terrorism police on Tuesday after a preliminary interrogated by police in the southern city of Antakya, near Syria. Newspapers have said the two were connected to Ekinci.
More than 130 people have been detained in connection to the bombings and 21 people — including Polat — have been charged, most with aiding or membership in an illegal organization.
On Monday, a Moroccan source in Raba said a senior al Qaeda operative suspected of ordering a deadly terrorist attack in Casablanca earlier this year may also have been behind bombings in Turkey.
Abu Musab al-Zarqawi, whom the CIA has described as a close associate of bin Laden, is believed to have played a role in attacks in Istanbul, said the source, who spoke on condition of anonymity.
Al-Zarqawi was identified by Moroccan authorities in July as the mastermind of a wave of suicide bombings that killed 33 bystanders and 12 suicide bombers in Casablanca in May.