Recep Tayyip Erdogan
Recep Tayyip ErdoganReuters

Turkish President Recep Tayyip Erdogan on Wednesday said the killer of Russia's ambassador to Turkey was a member of the group of Fethullah Gulen, his longtime rival who is blamed for the July 15 coup as well, AFP reports.

Off-duty Turkish policeman Mevlut Mert Altintas, 22, fired nine bullets at the ambassador, Andrei Karlov, at an art gallery in Ankara on Monday before he himself was killed by police in a shootout.

Pro-government press had already reported that police had discovered pro-Gulen literature belonging to Altintas, sympathizers of the preacher among his acquaintances and that he attended extra classes at a school belonging to the group.

"There is no need to make a secret out of the fact he was a member of FETO," Erdogan said on Wednesday, in his first clear attribution of blame for the murder.

Gulen currently resides in exile in the United States. He leads a popular movement called Hizmet and split from Erdogan over a corruption scandal in 2013. Erdogan has long accused him of running a parallel state from abroad.

Gulen was also accused by Turkey of orchestrating the failed July 15 coup plot but denies the claims. In fact, he has hinted that the uprising by members of the country’s military could have been “staged” by the government.

Turkey has embarked on a massive crackdown on what it calls the Fethullah Terror Organization (FETO) in the wake of the July 15 coup aimed at unseating Erdogan, arresting and sacking tens of thousands.

Erdogan said the assassination of Karlov showed Gulen supporters were still present within the key security structures and the purges needed to continue.

"I have to say this very clearly -- this dirty organization is still within the military, still within the police," he said, according to AFP.

Without expanding further, he added there could be "foreign connections" to the murder plot.

His comments come a day after Turkey’s Foreign Minister Mevlut Cavusoglu told his U.S. counterpart John Kerry that both Russia and Turkey believe that Gulen was behind Karlov’s assassination.

Turkey and Russia are jointly investigating the murder, but the Kremlin indicated it was not in the mood for rushed pronouncements on responsibility and made no mention of Gulen's purported involvement, according to AFP.

"In this case it is hardly worth hurrying to any conclusions until the investigation determines -- as our president said -- who was behind the murder of our ambassador," Kremlin spokesman Dmitry Peskov told reporters.

Eleven people, including close family members, have been detained over the killing and are being investigated for possible links to Gulen.