BAGHDAD (AP) - Two suicide bombers detonated explosives inside Baghdad's main police academy yesterday, killing at least 43 people and wounding more than 70, police said. Al-Qaida in Iraq claimed responsibility for the attack, the capital's deadliest in months.

The bombing came as Al-Jazeera aired an insurgent video claiming to have kidnapped a U.S. security consultant - the seventh Westerner abducted in Iraq since Nov. 26 - and the U.S. military reported another American soldier killed in a roadside bombing in Baghdad.

Late yesterday, another suicide bomber blew himself up in a cafe frequented by police in a Shiite neighborhood, killing three people and wounding 20, police said. One of the dead and three of the wounded were policemen, officials said.

The assault on the police academy was carefully planned to maximize casualties, all of whom were police officers or cadets.

The first bomber struck near a group of students outside a classroom, a U.S. military statement said.

Thinking they were under mortar fire, survivors rushed to a bunker "where the second bomber detonated his vest," the statement added. One of the wounded was an American contractor.

A statement on an Islamist website in the name of al-Qaida in Iraq said "two blessed brothers" staged the attack on the academy "which continues to produce the dogs that shed the blood and violate the honor of Sunni Muslims."

The claim's authenticity could not be independently verified, but al-Qaida in Iraq's leader, Abu Musab al-Zarqawi, has often denounced Shiites because of religious differences and their leading role in the U.S.-backed government. Shiites dominate the security services.

Iraqi police also said the attackers may have been policemen or students, fresh evidence that insurgents have infiltrated the country's security forces. President Bush has linked an eventual U.S. troop withdrawal to the ability of Iraq's army and police to combat the insurgents.

The attack was the deadliest against Iraqi security forces since Feb. 28, when a suicide car bomber struck a crowd of mostly Shiite police and army recruits in Hillah, killing 125. In September, at least 88 people were killed in a suicide car bombing in a heavily Shiite neighborhood of Baghdad.