Libyan security forces killed at least 24 people in a violent crackdown on anti-regime demonstrations during a "Day of Anger" against strongman Moammer Gadhafi, Human Rights Watch said Friday.

The New York-based rights group, citing witnesses, said 24 protesters were killed and scores injured during Thursday's assaults on protests in two Libyan cities.

Egypt has arrested two former government ministers and a businessman on suspicion of diverting public funds, a judicial source told Agence France Presse on Thursday.

Once widely feared former interior minister Habib al-Adly was also arrested on suspicion of money-laundering and ordered held for 15 days, the same source said.

Ousted Tunisian president Zine El Abidine Ben Ali suffered a stroke and was "in a coma" in a Saudi hospital, a family friend said Thursday, as more details of corruption under his rule came to light.

The 74-year-old former leader slipped into a coma "two days ago" while being treated in a Jeddah hospital after a stroke, according to the friend.

Bahrain's opposition demands the resignation of Prime Minister Khalifa bin Salman al-Khalifa's government following a deadly raid on anti-regime protesters, a Shiite opposition bloc said on Thursday.

"The opposition groups, including Al-Wefaq, have issued a statement demanding the government resign and calling for the formation of a new government to investigate this crime," said Al-Wefaq bloc's leader, Ali Salman.

Iranian officials were in contact with their counterparts in Egypt to secure the passage of two warships through the Suez Canal, Tehran's English-language Press TV reported on Thursday.

The vessels intend to transit the canal, the channel's website quoted an unnamed Iranian navy official as saying.

Arab foreign ministers of the Gulf monarchies are to hold an emergency meeting on Thursday in Manama, gripped by protests in which six people have been killed, Bahrain's foreign ministry said.

"The Gulf Cooperation Council states are expected to announce their support for the (Bahraini) government in security, defense and politically," said a ministry spokesman.

At least 12 people were injured and police fired warning shots during fierce clashes in Yemen's capital between anti-government protesters and regime loyalists on Thursday, an Agence France Presse correspondent said.

About 2,000 protesters, mostly students, had just left Sanaa University headed for the central Tahrir Square when they ran into regime supporters and clashes broke out for a fifth straight day, the reporter said.

At least four people were killed in clashes with Libyan security forces, opposition websites and NGOs said on Thursday, as the country faced a nationwide "Day of Anger" called by cyber-activists.

The websites monitored in Cyprus and a Libyan rights group based in London said the clashes with demonstrators opposed to the regime of Libya's leader Moammer Gadhafi took place on Wednesday in the eastern town of al-Baida.

Riot police stormed through a Manama Square in the dark early Thursday firing rubber bullets and tear gas in a harsh crackdown on anti-regime protesters that left four dead, witnesses and opposition said.

Up to 95 protesters were wounded when police launched the operation in the iconic Pearl Square without warning at around 3.00 am (midnight GMT), sending protesters fleeing in panic, they said.

Three Palestinians were shot dead by Israeli troops early on Thursday in an area near Gaza's northern border with Israel, officials on both sides said.

Adham Abu Selmiya, a spokesman for the Hamas-run emergency services, said the men died after being hit by a tank shell and machine gun fire in an area called Al-Waha which lies close to both the shore and the northern border with Israel.