SAN'A, Yemen -- Yemeni agents arrested five suspected members of an al-Qaida cell and uncovered evidence they were planning attacks against Western targets, a security official said Thursday.

The official, speaking on condition of anonymity, said six other suspected members of the cell are still at large, and at least one is thought to be hiding in neighboring Saudi Arabia.

The five suspects -- two Syrian men, two Yemeni men and a Yemeni woman -- were arrested when a police patrol stopped their car in San'a. They had computer discs with plans for assassinations and attacks against embassies, the official said.

Yemen, a target for suicide bombings in the past three years, has been an active participant in the U.S.-led war on terror, cracking down on Islamic extremists and agreeing to allow the FBI to open an office there.

The destroyer USS Cole was refueling in the Yemeni port of Aden in 2000 when suicide bombers attacked the boat, killing 17 U.S. sailors.

Yemen, located on the southern tip of the Arabian peninsula, is the ancestral home of al-Qaida leader Osama bin Laden.