A Turkish court on Monday charged nine suspected members of a group linked to Al Qaeda in an alleged plot to set off a bomb at a NATO summit in Istanbul next month that President Bush is scheduled to attend.

Private CNN-Turk television said three of the suspects had been plotting a suicide attack on Bush and other Western leaders at the summit, but officials could not confirm the report.

Authorities detained 16 alleged members of Ansar al-Islam (search) on Thursday in the northwestern province of Bursa, Gov. Oguz Kagan Koksal (search) said. The suspects also planned to attack a synagogue in Bursa and rob a bank to raise funds, Koksal said.

A Turkish court that deals with terrorism cases charged the nine with "membership in an illegal organization." Conviction on the charge carries a sentence of up to 10 years in prison.

Prosecutors earlier released the other seven suspects after questioning them. It was not clear if they could still face charges. No trial date has been set.

Nine others were questioned in Istanbul but also were released, officials said.

The crackdown on the group comes amid heightened security in the run-up to the June 28-29 meeting of NATO alliance leaders, following a series of bombings in Istanbul in November.

More than 60 people were killed when suspected members of a Turkish Al Qaeda cell bombed two synagogues, a London-based bank and the British Consulate. Turkish officials have charged 69 suspects in the bombings. Their trial starts later this month.

Istanbul, which will also host a European song contest this month and a meeting of foreign ministers from Islamic countries in June, is safe, said Gov. Muammer Guler.

"There is no question of a situation that will affect the (NATO) meeting," Guler said. "We have taken every precaution."

The Ansar al-Islam suspects appeared Monday in a court in Bursa, where they could face charges including membership in a terrorist group, possession of explosives, violating gun laws and holding fake identity documents. They were caught after yearlong police surveillance, Koksal said.

The group's leader, identified as Alpaslan Toprak, was among those detained, he said. Local TV showed him being escorted by police, grinning.

CNN-Turk said one of the suspects had been trained at a camp in Pakistan, where he stayed for six years.

Koksal said police also seized equipment to make remote-controlled bombs, guns, books on bomb-making, forged identity documents and CDs that served as training manuals.

"The group, which was in the middle of an attack plan, has been rendered ineffective," Anatolia quoted Koksal as saying.

Some of the suspects surveyed the site of a synagogue in Bursa as well as that of a bank, Koksal said.

He said the suspects planned to flee to Iraq to fight U.S. troops there once they had carried out a major attack in Turkey.

An Islamic group based in northern Iraq also goes by the name Ansar al-Islam and is suspected in the Feb. 1 bombings in Irbil that left 109 dead.

A police official, speaking on condition of anonymity, said the Turkish group and the northern Iraq group shared "the same ideology and tactics." The Turkish group increased in size in reaction to the U.S. war in Iraq, the official said.

Dogu Ergil, a professor of political science at Ankara University, said such plots were not unusual ahead of high profile events such as the NATO summit.

"The stage is important. The number of spectators is important. The NATO summit in Istanbul is an ideal stage for such (a terrorist) act to be staged," he said.

Earlier this month, authorities rounded up dozens of alleged members of the Revolutionary People's Liberation Party-Front (search), or DHKP-C, in simultaneous raids in Turkey, Italy, Germany, Belgium and the Netherlands.

The crackdown was seen as the result of increased international security cooperation before the NATO summit and the Athens Olympics in August.

According to Turkish newspapers, more than 30,000 police and other security forces, including hundreds of snipers, are expected to be on duty at the summit. Police also reportedly are watching anti-war, anti-globalization and other leftist groups, fearing they could stage protests or attacks.

The NATO summit will be the first since Romania, Bulgaria, Latvia, Estonia, Lithuania, Slovenia and Slovakia joined the alliance in April to increase its membership to 26 countries.