ISTANBUL (Reuters) – Turkish police have detained a suspected al Qaeda militant from Syria who they believe was organizing an attack on Israeli targets in Turkey, security sources said on Wednesday.

The suspect, believed to be the top figure in Osama bin Laden”s al Qaeda network in Turkey, was apprehended in the southeastern city of Diyarbakir on Sunday as he attempted to board a plane for Istanbul, the sources said.

The suspected militant, identified as Syrian national &#34Luia Sakra,&#34 was due to appear in an Istanbul court on Thursday, courthouse sources said.

Judges on Wednesday ordered the arrest of another Syrian national brought to the court on charges he is Sakra”s courier, the sources said.

Police earlier on Wednesday denied news reports that at least 10 al Qaeda-linked militants had been detained while planning attacks on foreign-flagged ships.

&#34The news reports that al Qaeda members have been caught with C-4 explosives as they prepared attacks on several foreign ships in the southern provinces are completely wrong and ill-intentioned,&#34 police headquarters said in a statement.

Private news channel NTV said that the group was gathering information on synagogues in Turkey as well as on Israeli ships to prepare for attacks.

It said the suspects were detained in Turkey”s largest city of Istanbul and in the Mediterranean tourism hub of Antalya.

The reports followed remarks by Israel”s counter-terrorism chief who on Tuesday said Turkey had caught al Qaeda-linked militants who were planning attacks against foreign tourists.

Israel this week diverted four cruise shops from Turkey to Cyprus and urged its citizens to avoid Turkey”s popular southern coast, citing &#34concrete and grave terror threats&#34 against them.

Security sources said Sakra, considered an expert bomb maker, had undergone plastic surgery and was attempting to fly to Istanbul under an assumed name for a second operation. He arrived in Diyarbakir from Antalya.

Sakra is thought to be responsible for al Qaeda”s cells in Turkey and to have played a key role in bombings in Istanbul in November 2003 that killed more than 60 people.

A Turkish al Qaeda cell claimed responsibility for those attacks, which struck two synagogues, the British consulate and London-based HSBC bank in one of Turkey”s worst episodes of peacetime violence.

Turkey has been on edge after a series of small and medium-sized bombings in recent weeks that have been blamed largely on Kurdish separatists.

Groups linked with the banned Kurdistan Workers Party (PKK) have claimed responsibility for two bombings in Aegean Sea tourism resorts last month, including one in which five people, including two foreign tourists, were killed.

Islamist militants, Kurdish separatists and left-wing radicals are all active in Turkey, the only mainly Muslim candidate for European Union membership.