KARACHI, Pakistan (AP) - An attacker crashed a -laden vehicle into a guard post outside the U.S. Consulate in Karachi on Friday,  himself and at least 10 others and injuring 45.

The massive blast incinerated a dozen cars, blew a 10-foot-wide hole in the compound wall and sent debris flying a half-mile.

No Americans were believed killed, but one U.S. Marine and five Pakistani employees in the consulate were slightly injured. The consulate has been operating with a skeleton staff since nonessential workers were sent home last month because of concerns for their safety.

In Washington, early U.S. suspicion centered on al-Qaida and affiliated Pakistani Islamic extremist groups, but officials said they had no direct evidence of who was responsible. Several Pakistani groups have ties to al-Qaida, but could have conducted the attack without the sanction of Osama bin Laden ( news - web sites)'s organization.

U.S. State Department officials said they would re-evaluate how many American personnel to keep in Pakistan.

"It's a deplorable act of ism and our condolences go to the families of the victims, and we wish a full and speedy recovery to all those injured," White House spokesman Sean McCormack said.

Some of the victims were blown apart, making it difficult to determine exactly how many people were killed.

But Dr. Hafiz Athar, a police surgeon, said 11 people were killed, including 10 identified by relatives or colleagues. The other set of remains was believed to be the er.

The victims included four Pakistani police constables, a male passer-by, the er and four women, police said. Three of the women had just finished a driver's education course and were getting their licenses.

The blast occurred less than a mile from the site where 11 French engineers and three others were killed in a  ing last month. It also came on the heels of a visit to Pakistan by U.S. Defense Secretary Donald H. Rumsfeld, who left the country Thursday.

No one claimed responsibility, but al-Qaida fugitives have taken refuge in Pakistan since the collapse of Taliban rule in neighboring Afghanistan ( news - web sites).

Police said the  was concealed in a white vehicle, believed to be a Suzuki van, that the driver crashed into a police kiosk at the southern end of the consulate at 11:08 a.m. (1:08 a.m. EDT).

The vehicle exploded after careering into one of the 3-foot-high, sand-filled concrete security barriers that encircle the compound. The barriers have gaps only wide enough to walk between.

The blast, heard several miles away, disintegrated the barrier, along with a 10-foot-wide section of the 10-foot-high, steel-reinforced wall behind it. Another barrier inside the wall was reduced to rubble, part of a huge tree was blown away, and windows in the four-story consulate were shattered.

Continued...The explosion also damaged the nearby Marriott Hotel and other buildings as far as a block away, including the Japanese Consulate, where a Japanese employee was injured slightly by flying debris.

Mark Wentworth, a U.S. Embassy spokesman in Islamabad, said six consulate employees — one U.S. Marine security guard and five Pakistani employees — suffered minor injuries when struck by flying debris.

He said the  exploded about 50 feet from the building, which sustained some structural damage.

Sharif Ajnabi, a private security guard, was sitting in a park across the street from the consulate.

"I heard a deafening explosion," he said. "There was smoke everywhere."

"Moments later, I saw a man's body flying in the air, and it fell near me. He was badly injured. Before we could give him water or medical help, he died. It was a horrifying scene."

As police sealed the area, emergency workers collected body parts and put them on sheets spread on the ground. Ambulances shuttled the injured to nearby hospitals. What appeared to be wreckage from the car was stuck in a water fountain and in trees.

The heavily secured consulate always has four layers of Pakistani and American guards. The sidewalk in front of the consulate normally is blocked and barricades shunt traffic away from lanes next to the building. Few people are allowed inside — even U.S. citizens have to make appointments days in advance.

"This is sheer ism," said Javed Ashraf Hussein, the chief secretary of Sindh province, who visited the scene of carnage. "We have put this area under high alert and heavy security, but the ists struck."

He would not comment on who might be responsible.

Karachi Mayor Naimat Ullah offered sympathy for U.S. officials and vowed to arrest those behind the attack.

"The ists have no religion. They are not Muslim. They are not human. They are just ists," Ullah said.

Violence against foreigners by Islamic militants has increased since Pakistani President Pervez Musharraf threw his support behind the U.S.-led war in Afghanistan.

Wall Street Journal reporter Daniel Pearl was abducted and ed in Karachi in January while working on a story about Islamic militants.

Suicide attacks — once unheard of here — have occurred twice. Both were believed to have been carried out by al-Qaida.

On March 17, a   attack at a church in Islamabad's diplomatic enclave killed five people, including two Americans.

Last month, 11 French engineers and three others were killed in a  ing in front of a Karachi hotel less than a mile from Friday's blast.

The United States withdrew all nonessential personnel from Pakistan after the church ing, and the British mission evacuated about 150 staff in late May after receiving "credible" information about a ist assault.

Also, in early June a diplomatic source said several hundred foreigners working for the United Nations ( news - web sites) in Pakistan were ordered to send their families home because of fears of a war between India and Pakistan.