Commandos burst into a Singaporean jetliner on the airport tarmac Wednesday and killed four Pakistani hijackers minutes before the terrorists said they would would start slaying passengers, officials said.

The attack on the hijackers, who were armed with knives and explosives, ended a nearly nine-hour ordeal for the 126 passengers and crew, who included three Americans. Two commandos and two crew members were slightly hurt.Communications Minister Yeo Ning Hong said it was over "in a matter of minutes" after the anti-terrorist squad struck.

Police said the hijackers, who seized the plane on a flight to Singapore from Malaysia, were demanding the release of a number of people detained in Pakistan, including the husband of former Prime Minister Benazir Bhutto.

Passengers said the hijackers had threatened to make an American their first victim and set fire to the plane.

An Australian passenger said one of the hijackers held a knife to the throat of an American man, saying he would be the first one killed.

"They seemed to be against Americans and blaming America for problems in their country," said Roger McGovern, a businessman from Sydney.

"These guys weren't playing games. They carried in their hands things that looked like huge (fire)crackers, eight inches long by three inches and knives six inches long," said McGovern, 48.

"They poured cognac around the plane and threatened to ignite it," McGovern said.

Singapore's Home Affairs Ministry confirmed that the cockpit, cabin floor and some passenger seats were doused with alcohol and the hijackers threatened to set fire to the plane.

The Singapore Airlines Airbus A310 was on a scheduled flight from Kuala Lumpur on Tuesday when it was commandeered.

U.S. Embassy spokesman Dennis Donohue said three Americans were on the flight but declined to identify them.