WASHINGTON: President George W. Bush demanded yesterday that those responsible for killing former Pakistani Prime Minister Benazir Bhutto be brought to justice.

“The United States strongly condemns this cowardly act by murderous extremists who are trying to undermine Pakistan’s democracy,” he said. “Those who committed this crime must be brought to justice.”

The president looked tense in delivering a brief statement to reporters at a hangar near his Crawford ranch in central Texas. He took no questions. His appearance came as U.S. officials here scrambled to cope with the immense policy implications involving a nuclear-armed country that has received billions in American financial assistance and has been an ally in the war on terrorism.

Bush expressed his deepest condolences to Bhutto’s family and to the families of others slain in the attack and to all the people of Pakistan. And the White House also reached out to Pakistani President Pervez Musharraf, said spokesman Scott Stanzel. He said Bush planned to speak with Musharraf as soon as it can be arranged later Thursday.

“Mrs. Bhutto served her nation twice as prime minister and she knew that her return to Pakistan earlier this year put her life at risk, yet she refused to allow assassins to dictate the course of her country,” Bush said.

“We stand with the people of Pakistan in their struggle against the forces of terror and extremism. We urge them to honor Benazir Bhutto’s memory by continuing with the democratic process for which she so bravely gave her life,” he said.

Bhutto was mortally wounded Thursday in a suicide attack that also killed at least 20 others at a campaign rally in Rawalpindi. She served twice as Pakistan’s prime minister between 1988 and 1996. She had returned to Pakistan from an eight-year exile Oct. 18. Her homecoming parade in Karachi was also targeted by a suicide attacker, killing more than 140 people. On that occasion she narrowly escaped injury.

U.S. officials _ who had labored to promote stability in the nuclear-armed country that has been an anti-terrorism ally _ huddled to assess the impact of Bhutto’s death two weeks before legislative elections in the turbulent nation in which her party was expected to do well.