Christians Under Attack

A U.S. embassy official confirmed that the blasts were caused by a car bomb and that there were reports of casualties.

"This morning a car exploded at the main gate of the embassy in Sanaa. There was an initial explosion and several secondary explosions," a U.S. embassy spokesman told Reuters by telephone.

"We do have reports of casualties. Right now, I cannot confirm the number, nor the nationality nor the severity of the casualties."

A group calling itself Islamic Jihad in Yemen claimed responsibility for the bombing and threatened attacks on other embassies including those of Britain, Saudi Arabia, and the United Arab Emirates.

It had threatened in a previous statement on Tuesday to launch a series of attacks unless the Yemeni government met its demands for the release of several members from jail.

"We, the organization of Islamic Jihad in Yemen declare our responsibility for the suicide attack on the American embassy in Sanaa," the statement read.

"We will carry out the rest of the series of attacks on the other embassies that were declared previously, until our demands are met by the Yemeni government."

Smoke was seen rising from the heavily fortified U.S. compound in Sanaa and ambulances and fire engines raced to the scene, which was cordoned off by police, witnesses said.

The security source said that six attackers and four bystanders were killed, while the rest were Yemeni security forces.

Yemen, the ancestral home of Osama bin Laden, has grappled with a spate of al Qaeda attacks this year, including one on the U.S. embassy, another near the Italian mission and others on Western tourists.

An al Qaeda-affiliated group claimed responsibility in March for a mortar attack that missed the U.S. embassy but wounded 13 girls at a nearby school.

The United States ordered non-essential staff to leave Yemen in April, a day after an attack on a residential compound.

The Yemeni government joined the U.S.-led war against terrorism following the September 11 attacks on U.S. cities in 2001.

It has jailed dozens of militants in connection with bombings of Western targets and clashes with authorities, but is still viewed in the West as a haven for Islamist militants.

The government of the poor Arab country has also been fighting Shi'ite rebels in the northern province of Saada since 2004 and faced protests against unemployment and inflation.

(Reporting by Abdul-Rahman Alansi in Yemen, Lin Noueihed and Raissa Kasolowsky in Dubai; Writing by Lin Noueihed; Editing by Alison Williams)