DAMASCUS, Syria, (AP)- Islamic militants attempted to storm the U.S. Embassy in Damascus on Tuesday using automatic rifles, hand grenades and at least one van rigged with explosives, the government said. Four people were killed in the brazen attack, including three of the assailants.

No Americans were hurt, and the attackers apparently did not breach the high walls surrounding the embassy’s white compound in the city’s diplomatic neighborhood.

But one of Syria’s anti-terrorism forces was killed and at least 11 others were injured, the country’s official news agency reported. The wounded including a police officer, two Iraqis and seven people employed at nearby technical workshop.

A Chinese diplomat also was hit in the face by shrapnel and slightly injured while standing on top of a garage at the Chinese Embassy, China’s government news agency said.

A witness said one Syrian guard outside the embassy also was killed, but the government did not immediately confirm that. At the embassy in Damascus, as at most American embassies worldwide, a local guard force patrols outside the compound’s walls while U.S. Marine guards are mostly responsible for guarding classified documents and fighting off attackers inside the compound.

Witnesses also said the gunmen tried to throw hand grenades into the embassy compound, shouting “Allah Akbar!” or “God is great!” It was not clear if any of the grenades made it over the walls, which are about 8 feet high.

The attack came at a time of high tension between the United States and Syria over the recent Israeli-Hezbollah war in neighboring Lebanon. In Damascus the sentiment has become increasingly anti-American sentiment.

Syria has seen previous attacks by Islamic militants. In June, Syrian anti-terrorism police fought Islamic militants near the Defense Ministry in a gunbattle that killed five people and wounded four.

After Tuesday’s attack, pools of blood lay splattered on the sidewalk outside the embassy, along with a burned car apparently used by the attackers. A sports utility vehicle with U.S. diplomatic tags had a bullet hole through its front window, and the glass windows of nearby guard houses also were shattered.

There were conflicting reports of what happened.

Syrian TV said one car was rigged with explosives but never was detonated by the attackers. But one witness said a second car did explode, and TV footage from the scene showed a burned car.

The Syrian Interior Ministry, which is in charge of police, said a fourth attacker now in detention was wounded in the incident, which it called a “terrorist attack.” The report, carried on state-run television, said anti-terror units brought “the situation under control” and an investigation was under way.

In Washington, a State Department spokesman confirmed the attack by “unknown assailants” but had few details.

“Local authorities have responded and are on the scene,” said spokesman Kurtis Cooper said. He said he had no further information.

A U.S. Embassy statement said the embassy came under armed attack at 10:10 am local time and that all embassy personnel are safe. One Syrian embassy guard was injured by gunfire and is in a stable condition at a local hospital, the statement said.

The Embassy’s charge d’affairs, Michael Corbin, met with Syrian Interior Minister Bassam Abdel Maguid at the scene, and spoke by phone with assistant minister of foreign affairs, Ahmed Arnous, according to the statement.

It said the Syrian government has pledged full security cooperation.

State television said four armed attackers “attempted to storm” the Embassy, using automatic rifles and hand grenades. Syrian security guards attacked the gunmen, killing three and wounding a fourth, TV said.

The attackers came in two cars and parked one that was rigged with explosives in front of the embassy but did not blow it up, state-run TV reported. Explosive experts dismantled the bomb, it said.

But a witness told The Associated Press that two gunmen stopped a car on the street in front of the embassy, got out of the car, shot at the Syrian sentries in front of the building’s entrance and then detonated the car.

The witness, who spoke on condition of anonymity because of the sensitivity of the matter, said the security personnel shot back, and security forces in the area rushed to the scene.

Television footage showed a delivery van loaded with pipe bombs strapped to large propane gas canisters outside the Embassy. Had the bombs detonated, the explosions would have caused massive damage.

The footage also showed the charred remains of a smaller car parked several feet behind the van.

A Syrian who works at the American Embassy, contacted by telephone, said there were no U.S. casualties. The employee, who spoke on condition of anonymity, said the incident started just after 10 a.m.

Damascus has been hit by militant attacks in the past. In April 2004, four people were killed in a clash between Syrian police and a team of suspected bombers in the diplomatic quarter of Damascus.

The authorities at that time accused Islamic militants of trying blow up an explosives-laden car near the Canadian embassy.