Washington, DC — The State Department has announced that the U.S. embassy in Nairobi, which was closed Friday because of what officials termed "a serious terrorist threat," will remain closed on Monday and Tuesday.

The closure followed a decision by the Pentagon to raise the threat level in Kenya to 'high', U.S. officials said. 'High' is the most serious of four terrorism warning levels

In November, attacks on an Israeli-owned hotel and airliner in Mombasa left 16 people dead, including 10 Kenyans and three Israelis. Al-Queda reportedly claimed responsibility. In 1998, car bomb explosions at U.S. embassies in Nairobi and Dar es Salaam, capital of neighboring Tanzania, killed 224 people, most of them Africans.

State Department spokesman Phillip Reeker said Friday that the closure would allow the embassy "to review its security posture." While American embassies in the region, and in many parts of the world, are shut down periodically for security concerns, officials said this action was prompted by specific information about planned activity. The information is highly classified, the officials said.

The embassy is housed in a new, high-security facility that was built after the 1998 bombing in Nairobi.