Amman, Jordan ? Suicide bombers carried out nearly simultaneous attacks on three U.S.-based hotels in the Jordanian capital Wednesday night, killing at least 57 people and wounding 115 in what appeared to be an al-Qaida assault on an Arab kingdom with close ties to the United States.

The explosions hit the Grand Hyatt, Radisson SAS and Days Inn hotels just before 9 p.m. One of the blasts took place inside a wedding hall where 300 guests were celebrating – joined by a man strapped with explosives who had infiltrated the crowd. Black smoke rose into the night, and wounded victims stumbled from the hotels.

Jordan’s deputy prime minister, Marwan Muasher, said there was no claim of responsibility but that Abu Musab al-Zarqawi, the Jordanian-born leader of al-Qaida in Iraq, was a “prime suspect.”

A U.S. counterterrorism official, who spoke on condition of anonymity because the investigation is ongoing, said the strong suspicion is that al-Zarqawi was involved because of his known animosity for Jordanian monarchy and the fact that it was a suicide attack, one of his hallmarks.

A firefighting vehicle enters the main gate of the Radisson Hotel in Amman after explosions Wednesday rocked three hotels in Jordan's capital. The explosions struck the Grand Hyatt, Radisson SAS and Days Inn hotels and killed 57 people and injured at least 115.

In February, U.S. intelligence indicated that Osama bin Laden was in contact with al-Zarqawi, enlisting him to conduct attacks outside of Iraq. Jordan has arrested scores of Islamic militants for plotting to carry out attacks and has also sentenced many militants to death in absentia, including al-Zarqawi.

Its capital has become a base for Westerners who fly in and out of neighboring Iraq for work. Amman’s main luxury hotels downtown are often full of American and British officials, and contractors enjoying the relative quiet of the city.

A State Department official said there was no information on any American casualties. A Jordanian security official, speaking on condition of anonymity because he was not authorized to address the media, said the dead included at least three Asians.

The first blast was reported about 8:50 p.m. at the Grand Hyatt. The explosion took place in the lobby and shattered its entrance.

A few minutes after that attack and a short distance away, police reported the explosion at the wedding celebration, which took place in a special reception hall on the ground floor of the Radisson. At least five people were killed and 20 wounded.

The third explosion, at the Days Inn, happened after a car packed with explosives approached the hotel, Muasher said. He said the car could not cross a protective barrier so it detonated outside. As a result, the casualties at the Days Inn were not so extensive as at the other hotels, he said.

Muasher reported 57 killed and 115 wounded in the three bombings, with the worst damage at the Radisson because the suicide bomber got inside the wedding party of Jordanians.