Controversial Arab-Israeli Islamist leader Sheikh Raed Saleh has been arrested in London after entering Britain in defiance of a government ban, Home Secretary Theresa May said Wednesday.

The British authorities have begun arrangements to deport Saleh, who is the head of the radical northern wing of the Islamic Movement in Israel, and have launched an investigation into how he managed to enter the country, she said.

A Yemeni air raid on a convoy of vehicles near the militant-held southern city of Zinjibar killed four civilians and wounded 12 on Wednesday, medical sources and witnesses said.

The convoy that was hit had left Zinjibar for the main southern city of Aden but was forced to come to a halt when fighting erupted between government troops and the militants, witnesses said.

Iranian President Mahmoud Ahmadinejad on Wednesday warned the authorities against making arrests of members in his government whom he vowed to defend, the official IRNA news agency reported.

"I consider defending the cabinet as my duty... the cabinet is a red line and if they want to touch the cabinet, then defending it is my duty," Ahmadinejad was quoted as telling reporters after a cabinet meeting.

Around 50 people were injured in overnight clashes between protesters and police in central Cairo, officials said, as new scuffles erupted on Wednesday morning.

Anti-riot police were deployed around Tahrir Square -- the epicenter of protests that toppled President Hosni Mubarak in February -- and near the interior ministry building in central Cairo, an Agence France Presse reporter said.

France has begun parachuting arms shipments to Berber rebels fighting Libyan leader Moammar Gadhafi's forces in the highlands south of Tripoli, the French daily Le Figaro reported on Wednesday.

According to the paper, which said it had seen a secret intelligence memo and talked to well-placed officials, the air drops are designed to help rebel fighters encircle Tripoli and encourage a popular revolt in the city itself.

Dozens of tanks and other armored vehicles entered the Syrian village of al-Rami, in the province of Idlib, on Tuesday, Rami Abdul Rahman, president of the Syrian Observatory on Human Rights said.

Separately, other anti-regime militants said Syrian forces had opened fire there and set off flares, which could be seen from the neighboring village of Irm al-Joz.

Britain on Tuesday summoned the Syrian ambassador to express concerns about reports that a diplomat at the embassy had been intimidating Syrians in Britain, the foreign ministry said.

"Syrian Ambassador Dr. Sami Khiyami was invited in to see the (Foreign and Commonwealth Office) Middle East Director Christian Turner," said a foreign ministry statement.

The Syrian regime's authorization of an opposition meeting is a "move in the right direction," but President Bashar al-Assad still needs to go further, the United States said Tuesday.

About 160 dissidents, several of whom have spent years in jail as political prisoners, gathered Monday, prompting the U.S. State Department to say it was "pleased to see the opposition has been allowed some breathing space."

Gulf troops sent to back Bahraini security forces in their crackdown on Shiite-led protests are to be "redeployed" but will not withdraw completely, a Saudi official said on Tuesday.

"It is normal to redeploy the Peninsula Shield force but the danger is not over yet and these forces will not return to their bases or entirely withdraw," the official told Agence France Presse.

Anti-regime activists behind street protests in Syria on Tuesday criticized opposition figures who held an unprecedented meeting in Damascus at which they called for a peaceful uprising.

"As a matter of principle, the Coordination Committees of the Syrian Revolution condemn any meeting or congress held under the banner of the regime," they said on their Facebook page, an engine of the revolt.