UPDATE 1-Syria protesters hurl rocks at China embassy in Libya

(Adds details, end of demonstration)

TRIPOLI Feb 6 (Reuters) - Syrian and Libyan demonstrators hurled rocks, eggs and tomatoes at the Chinese embassy in Tripoli on Monday, after Russia and China vetoed a U.N. Security Council resolution backing an Arab plan urging Syria's President Bashar al-Assad to give up power.

Armed men, who said they were from the Libyan government's Supreme Security Committee, guarded the embassy from about 50 protesters who waved Syrian opposition flags and had managed to break windows and spray graffiti on the walls.

One demonstrator tried to force his way past the guards but was stopped, a Reuters reporter said.

Just as protesters had done the day before at the Russian embassy, demonstrators said they wanted to take down the Chinese flag and replace it with the Syrian opposition's flag and the red, black and green flag of Libya's National Transitional Council (NTC), which came to power after a civil war last year that toppled and killed Muammar Gaddafi.

"All of this is because of what is happening in Homs, this is because of the Chinese and Russian veto," Ahmed Mourad a Syrian expatriate in Libya, said.

One of the men guarding the embassy said his colleagues had shot into the air to disperse the crowd when they hurled rocks and tried to push their way through. The crowd later hurled eggs before lining up to pray at prayer hour.

A Reuters reporter was let inside the compound. A Chinese security guard who spoke to him at the door of the embassy building and gave his name as Ibrahim said: "We are fine."

A Libyan government guard parked a vehicle mounted with an anti-aircraft gun in front of the door of the compound, pointing outwards, and placed the Syrian opposition and Libyan NTC flags in the barrel to loud cheers from the crowd.