SANAA, Yemen – Yemeni police with clubs Saturday beat anti-government protesters who were celebrating the resignation of Egyptian leader Hosni Mubarak and demanding the ouster 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 Mubarak. His ouster raised questions about the long-term stability of Yemen and other Western-allied governments in the region.

The United States is in a delicate position because it advocates democratic reform, but wants stability in Yemen because it is seen as a key ally in its fight against Islamic militants.

Hundreds of protesters had tried to reach the Egyptian embassy in Sanaa, Yemen’s capital, on Saturday, but security forces pushed them back. Buses ferried ruling party members, equipped with tents, food and water, to the city’s main square to help prevent attempts by protesters to gather there.

There were about 5,000 security agents and government supporters in the Sanaa square named Tahrir, or Liberation. Egypt’s protesters built an encampment at a square of the same name in Cairo, and it became a rallying point for their movement.