Baghdad, Iraq ? Two suicide bombers detonated explosives inside Baghdad’s main police academy Tuesday, killing at least 43 people and wounding more than 70. Al-Qaida in Iraq claimed responsibility for capital’s deadliest attack 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 Tuesday, another suicide bomber blew himself up in a cafe frequented by police in a Shiite neighborhood in Baghdad, killing three people and wounding 20, police said. One of the dead and three of the wounded were policemen, officials said.

The violence came as Saddam Hussein’s trial continued in Baghdad, with the ousted leader defiantly telling the judges to “go to hell” and vowing not to return to court today.

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.

This image from the Arab satellite news channel Al Jazeera purports to show a kidnapped U.S. security consultant. The authenticity of the video could not be confirmed Tuesday.

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.

“We were sitting in the yard when we heard an explosion,” said police Maj. Wisam al-Heyali. “Seconds later, we were hit by another explosion as we were running. I saw some of my colleagues falling down and I felt my hand hit, but I kept on running.”

Evidence of infiltration

A statement on an Islamist Web site 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.

Iraqi police also said the attackers may have been policemen or students, fresh evidence that insurgents have infiltrated the country’s Shiite-dominated 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.

U.S. and Iraqi officials have warned of an increase in insurgent attacks ahead of the Dec. 15 elections. Ramadi residents reported seeing fliers Tuesday in the name of al-Qaida in Iraq warning people not to vote and threatening to bomb polling stations.

Police Capt. Jalil Abdul-Qadir said 43 people were killed, including seven policewomen, and at least 73 wounded in the attack on the academy. U.S. forces said the death toll was at least 27.

Also Tuesday, the U.S. military said a soldier assigned to Task Force Baghdad was killed when a patrol hit a roadside bomb Sunday. At least 2,129 members of the U.S. military have died since the Iraq war started in March 2003, according to an Associated Press count.

Hostage investigation

The video broadcast on Al-Jazeera showed a blond, Western-looking man sitting with his hands tied behind his back. The video also bore the logo of the Islamic Army in Iraq, an insurgent group, and showed a U.S. passport and an Arabic identification card with the name Ronald Schulz. The spelling of the name was uncertain because it was written in Arabic.

U.S. Embassy spokeswoman Liz Colton said American authorities were aware of the Al-Jazeera report and were investigating.

The authenticity of the video could not be confirmed.

If true, the man would be the second American taken hostage in the last two weeks. A U.S. citizen was among four peace activists abducted Nov. 26 by a group calling itself the Swords of Righteousness. Two Canadians and a Briton also were seized.

The British Broadcasting Corp. aired a video Tuesday in which the captive peace activists urged British Prime Minister Tony Blair and the United States to pull out of Iraq.

The excerpt was a previously unseen section of a video broadcast last week by Al-Jazeera in which the group threatened to kill the four men unless all prisoners in U.S. and Iraqi detention centers are freed by Thursday, according to the BBC, which said it obtained the new footage from the Internet.

“I ask Mr. Blair to take British troops out of Iraq and leave the Iraqi people to come to their own decisions on their government,” a British-accented male voice, presumably that of Briton Norman Kember, said.

A male voice with a North American accent then said: “As a representative of Christian Peacemaker Teams, we feel that continued American and British occupation is not in the best interest of the Iraqi people.”

On Tuesday, Bush said the United States will work for the return of captive Americans in Iraq but would not submit to terrorist tactics.

“We, of course, don’t pay ransom for any hostages,” Bush said. “What we will do, of course, is use our intelligence-gathering to see if we can’t help locate them.”

A French engineer was taken hostage in Baghdad on Monday and a German aid worker was abducted near Mosul on Nov. 26.