Updated

A court charged nine people in the homicide attacks against British targets in Istanbul (search) Tuesday as Britain warned that more violence against Western interests could be in the offing.

The nine were believed to be accomplices of the two homicide bombers in last week's attacks against the British Consulate and a branch of a London-based bank. Six others have already been charged in the Nov. 15 homicide attacks on two synagogues in Istanbul.

As many as seven more suspected accomplices -- including one with Swedish citizenship -- were being held for questioning and were expected in court Wednesday, according to a televised report. There was no official confirmation.

The British government warned that it had information suggesting "further attacks may be imminent in Istanbul and Ankara." In a statement Tuesday, the Foreign Office advised citizens to be vigilant, particularly around potential targets, such as Western interests and symbols of the Turkish state.

Officials have said two double bombings, which killed a total 57 people, were carried out by Turkish militants with help from abroad, perhaps from Al Qaeda (search). The role of Turks in the attacks has shaken many in this majority Muslim but officially secular nation.

Prime Minister Recep Tayyip Erdogan (search), in a televised address on the eve of Eid al-Fitr, the three-day holiday ending the Muslim fasting month of Ramadan, appealed to Turks to resist terrorism.

"This is a war between justice and cruelty, good and bad, and true and false," Erdogan said. "It is our right to expect every sensible person to stand by justice, good, and truth in this war."

Under government instructions, sermons in mosques around the country carried an anti-terrorism message Tuesday ahead of the Eid's start.

Meanwhile, Turkish warplanes were reportedly alerted across Turkey against preventing a possible Sept. 11-type attack by terrorists with a plane, the daily Milliyet reported. Turkish military declined to comment on the report.

As a security measure, police shut down a gate at Istanbul Ataturk Airport where passengers on private and small planes board.

The suspects in the bombings of the British targets were brought into a security court Monday, their heads covered with jackets and coats, and questioned for hours. Outside, a police line held back a crowd of shouting relatives, including several women wearing black chadors, the all-covering Islamic garment rare in downtown Istanbul.

On Tuesday, the court charged eight with being members of an illegal organization, and one was accused of aiding and abetting an illegal organization. Authorities declined to say which group the suspects allegedly belonged to.

The charges are punishable by up to five years in prison, and no trial date was set. Three other suspects were released, defense lawyer Selahattin Karahan said.

The people charged earlier in the synagogue bombings belonged to Beyyiat el-Imam, a little-known group formed in Al Qaeda camps in Afghanistan whose name is Arabic for "Allegiance to the Imam," the daily Cumhuriyet reported Tuesday, citing police. Police would not confirm the report.

Turkish media said the two bombers in the consulate and bank attacks were militants previously reported to be accomplices of the homicide bombers in the synagogue attacks.

In Ankara, police detained 10 suspected members of a little-known militant group, Warriors of Islam, the daily Hurriyet reported Tuesday.

The suspects were believed to have links to Azad Ekinci, who the press says has been identified as one of Thursday's homicide bombers. Police said the 10 underwent military training in Afghanistan and Iran and were planning attacks, the newspaper said. Police refused to confirm the report to The Associated Press.

Istanbul's governor, Muammer Guler, said Monday that DNA tests had identified the bomber who rammed an explosive-packed pickup truck into British consulate.

"We've identified the culprits who carried out the attack on the British Consulate," Guler said. "We have all the details and we know their connections."

Guler would not name the man; but the Istanbul newspaper Milliyet defied government reporting restrictions and identified him as Feridun Ugurlu, a Turk believed to have fought with Islamic radicals in Afghanistan and Chechnya. Ekinci was identified as the bomber of the bank offices, according to newspapers.

Police have examined the hard drives of 10 computers taken after the synagogue bombings from an Internet cafe in the city of Bingol, believed to be the hometown of at least three homicide bombers. The cafe belonged to the brother of one of the suspected bombers, a local official said by telephone.

Bingol is a hotbed of the radical Islamic group Hezbollah.

Experts speculate that Hezbollah, which is different from the Lebanese Shiite group of the same name, may have been backed by Turkish authorities in the early 1980s to counter Kurdish separatists in the southeast. Turkey now sees the group as a threat to the secular state and is investigating any links to Al Qaeda.