ABBOTTABAD, Pakistan—Under powerful floodlights and surrounded by rings of soldiers and police, heavy machines began Saturday night to demolish the three-story compound in northwestern Pakistan where Osama bin Laden lived for years and was killed by U.S. commandos last May.

Each blow helped eliminate a concrete reminder of the painful and embarrassing chapter in Pakistan's history that the al-Qaida chief's discovery and death in a town not far from the nation's capital represented.

Pakistan was outraged by the covert American raid in Abbottabad because it was not told about it beforehand -- a decision the U.S. explained was driven by concerns that someone in the government might tip off bin Laden.

The terror leader's death was cheered across the globe, but many Pakistanis were angry that the U.S. violated its territory and that its troops were powerless to stop American soldiers from attacking a compound located next to the country's equivalent of West Point, the elite U.S. military academy.

Just as U.S. Navy SEALs waited for the cover of darkness to descend on bin Laden's compound by helicopter from neighboring Afghanistan, Pakistani authorities held off on tearing it down Saturday until the sun had set, said local residents.

They brought in at least three machines equipped with powerful crane-like arms during the afternoon and also set up floodlights that allowed them to begin work at night, said the residents, who spoke on condition of anonymity because they were afraid of being harassed by the government.

A large team of police set up an outer cordon around the compound to keep spectators and journalists away, said an Associated Press reporter who managed to get close enough to see the demolition work under way. A ring of army soldiers set up an inner cordon and warmed themselves against the winter chill by lighting a bonfire.

The bulldozers broke through tall outer boundary walls that ringed a courtyard where one of the U.S. helicopters crashed during the operation to kill bin Laden. They then began to tear down the compound itself.

A Pakistani intelligence official confirmed that the demolition was in progress but declined to say why the government chose to do it. He spoke on condition of anonymity because he was not authorized to talk to the media.

The government did not give advance warning that it planned to tear down the compound.