Thousands streamed into Yemen’s capital trying to bolster anti-government demonstrators after club-wielding backers of President Ali Abdullah Saleh tried to drive them out

Thousands streamed into a square in Yemen's capital, Sanaa, on Wednesday, trying to bolster anti-government demonstrators after club-wielding backers of President Ali Abdullah Saleh tried to drive them out.

Security forces used tear gas and fired bullets in the air to disperse protesters in Aden, and two demonstrators were reported to have been martyred and 18 wounded during the attack. Since the unrest began two weeks ago, 15 people have reportedly been martyred.

Protesters, who have been demonstrating daily ovr the past few weeks, have been confronted not only by security forces but also by armed government loyalists staging counter-protests.

Seven MPs resigned from Saleh's ruling General People's Congress party because of the situation in the country and said they will form an independent bloc, according to a member of parliament, Abdul-Aziz Jabbari. The resignations raise to nine the number of legislators who have left the party since protests began.

The U.S.-backed Saleh, in power for 32 years, has said that he will step down after national elections are held in 2013. But a widening protest movement, inspired by successful uprisings in Egypt and Tunisia, is demanding that he leave office now.

Saleh had reportedly asked security forces to thwart all clashes in Yemen. "Ali Abdullah Saleh instructed all security services to thwart all clashes and prevent direct confrontation between pro- and anti-government protesters," Al Arabiya quoted an official statement. "The government...will continue to protect the rights of its citizens to assemble peacefully and their right to freedom of expression," the statement said.