Pakistan authorities have seized two vehicles carrying about 2,200 pounds of explosives, foiling a possible terror plot near Pakistan's capital, officials said.

Senior police officer Rao Mohammed Iqbal told The Associated Press that several suspects were arrested in the operation late Thursday in the garrison city of Rawalpindi — just days after a suicide car bombing against the Danish Embassy in Islamabad this killed six people.

Two security officials, who spoke on condition of anonymity because they were not authorized to speak to media, said Friday at least three men were arrested and were being questioned by civil and military authorities in Rawalpindi.

The men were suspected of wanting to target "sensitive installations," the officials said. Iqbal said the operation had "foiled possible terrorist attacks" but provided no details.

Rawalpindi houses the headquarters of Pakistan's army and the residence of President Pervez Musharraf, a longtime U.S. ally in its war on terror.

Iqbal, the deputy inspector-general of Rawalpindi police, said the two vehicles were laden with explosives, but did not say whether they had been rigged up to detonate.

An Internet posting Thursday purportedly from Al Qaeda in Afghanistan claimed responsibility for Monday's bombing outside the Danish Embassy and threatened to "rain" more attacks on countries where cartoons of the Prophet Muhammad are published.

The attack was the deadliest strike against Denmark since the publication of cartoons' in newspapers there and other Western countries sparked violent unrest across the Muslim world. In February, Danish papers reprinted one drawing of Muhammad in a bomb-shaped turban.

Rawalpindi lies about seven miles from Islamabad.