Yemeni police with clubs have beaten up anti-government protesters who were celebrating the resignation of Egyptian leader Hosni Mubarak and demanding the ousting of their own president.
The crackdown reflected an effort to undercut a protest movement seeking fresh momentum from the developments in Egypt, where an 18-day uprising toppled Mr Mubarak.
His departure raised questions about the long-term stability of Yemen and other Western-allied governments in the region.
Hundreds of protesters had tried to reach the Egyptian embassy in Sanaa, Yemen’s capital, but security forces pushed them back.
Egypt’s protesters built an encampment at Tahrir Square, the same name as the main square in Cairo, and it became a rallying point for their movement.
The demonstrators tore up pictures of President Ali Abdullah Saleh and shouted slogans demanding his immediate resignation.
Buses ferried about 5,000 ruling party members, equipped with tents, food and water, to the city’s main square to help prevent attempts by protesters to gather there.
Witnesses said police, including plainclothes agents, drove several thousand protesters away from Sanaa’s main square.
Mr Saleh has been in power for three decades and has tried to blunt unrest by promising not to run again. His term ends in 2013.
Yemen is the Arab world’s most impoverished nation and has become a haven for al Qaida militants. Mr Saleh’s government is riddled with corruption and has little control outside the capital. Its main source of income – oil – could run dry in a decade.