Updated

An Islamic extremist wanted by Germany for allegedly calling for terrorist attacks on Europe has been arrested in Turkey and Berlin is negotiating his extradition, an official said Friday.

Mohamed Mahmoud, 27, was picked up Tuesday in the southeastern province of Hatay near the Syrian border, a German security official with knowledge of the talks said. The official spoke on condition of anonymity because he was not authorized to discuss the matter. He said Germany has already begun preliminary proceedings to have Mahmoud extradited.

"We are very confident we will get him to Germany," he said.

Mahmoud was jailed in his native Austria in 2007 for being a leader of the Global Islamic Media Front, which creates and distributes terrorist propaganda videos. Among the accusations, police said he threatened both Austria and Germany with attacks if they did not withdraw military personnel from Afghanistan.

Following his release in 2011, Mahmoud moved to Germany and became an imam with the ultraconservative Salafi movement, which has been growing rapidly in the country by attracting both Muslims and converts. They have been under close observation since 2010, but that was stepped up further last year after they clashed with police in Bonn last year at a rally of a far-right party.

His group, Millatu Ibrahim, was banned last June. Officials at the time said it taught followers to reject German law and follow Islamic Shariah law and that "the unbelievers are the enemy." Mahmoud, who had already been expelled from Germany ahead of the ban, resurfaced in Egypt -- where his father is from -- and called on his followers to join him. German security officials say dozens of "jihad travelers" responded, traveling to Egypt and then going on to fight elsewhere -- largely in Mali, Syria and Yemen.

While in Egypt, Mahmoud is also alleged to have produced online German-language videos for the Global Islamic Media Front calling for terrorist attacks in Europe.

It was not immediately clear when he left Egypt nor whether he was on his way to Syria when he was arrested in Turkey.

Police officials in Ankara and Hatay province said they did not have any information on the arrest. The Austrian Foreign Ministry said it was aware of the arrest but said the man's identity had not yet been confirmed.