BAGHDAD, Iraq (AP) – An American soldier was killed in a roadside bombing north of Baghdad, the U.S. military said Friday, making April the deadliest month for American forces in Iraq this year.

American troops, acting on tips from Iraqi intelligence, killed the reputed al-Qaida boss of Samarra, where a Shiite shrine bombing two months ago nearly plunged the country into civil war.

The latest American death, which occurred Thursday evening, brought the number of U.S. troops who have died this month in Iraq to at least 69.

Although that figure is well below some of the bloodiest months of the Iraq conflict, it marks a sharp increase over March.

In March, 31 American service members were killed. January’s death toll stood at 62 and February’s at 55. In December 2005, 68 Americans died.

Reasons behind the rising U.S. deaths were unclear, and U.S. military officials have cautioned not to interpret cyclical changes as the beginning of a trend. Some U.S. officers have suggested the increase could be due to better weather this month, making it easier for insurgents to launch attacks.

The increase in U.S. deaths comes at a time when the U.S. military says sectarian violence among Iraqis is declining after a sharp rise in the wake of the Feb. 22 bombing in Samarra. That triggered reprisal attacks against Sunni mosques and clerics.

In a briefing Thursday, Maj. Gen. Rick Lynch told reporters sectarian attacks in the Baghdad area had fallen by 60 percent last week, diminishing fears of civil war.

That could also indicate militants were shifting their attacks on U.S. and Iraqi forces, their traditional targets throughout the three-year insurgency.

Al-Qaida in Iraq leader Abu Musab al-Zarqawi warned in an Internet video earlier this week that U.S. “dreams” in Iraq “will be defeated” and “what is coming is even worse.”

The 16-minute video by al-Zawahri, posted Saturday on an Islamic militant Web forum, also came within the same week as an audiotape by al-Qaida’s top leader Osama bin Laden.

Al-Zawahri said that al-Qaida in Iraq “alone has carried out 800 martyrdom operations (suicide attacks) in three years, besides the sacrifices of the other mujahedeen, and this is what has broken the back of American in Iraq.”

The video was first obtained by IntelCenter, a U.S. contractor that provides counterterrorism intelligence services to the U.S. government. A U.S. counterterrorism official, speaking on condition of anonymity in compliance with office policy, said it was part of al-Qaida’s ongoing propaganda blitz to demonstrate the terror group remained relevant.

In a possible sign of a shift, insurgents launched simultaneous attacks Thursday on police stations and checkpoints around Baqouba, 35 miles northeast of Baghdad.

At least 58 people were killed and 74 arrested in two days of clashes, Maj. Gen. Ahmed al-Awad said. They included 49 insurgents, seven Iraqi soldiers and two civilians, Iraqi and U.S. officials said.

The raid on the purported al-Qaida in Iraq safehouse took place Friday about nine miles north of Samarra, U.S. officials said. The target of the raid, Hamadi Tahki al-Nissani, was killed when he tried to escape, and two other insurgents were killed, one as he tried to throw a grenade, a U.S. statement said. Samarra, 60 miles north of Baghdad, was an al-Qaida in Iraq stronghold until U.S. troops regained control two years ago.

Separately, the spokesman of a Sunni Arab political party, Dhafer al-Ani, told Iraqi state television that two members of an undisclosed militia group have been detained in the slaying of Vice President Tariq al-Hashimi’s sister.

Mayson al-Hashimi, 60, was slain Thursday by gunmen firing from a car as she left her home in a southwestern neighborhood. Her bodyguard was also slain. Two weeks ago, the vice president’s brother, Mahmoud al-Hashimi, was shot and killed while driving in a mostly Shiite area of Baghdad.

Interior Ministry officials said they were unaware of any arrest. Al-Ani told The Associated Press he learned of the arrests from the Iraqi army.

Also Friday, former leader Saddam Hussein, who is being tried in Iraq on charges of crimes against humanity, turned 69. Small pro-Saddam rallies were staged in his hometown of Tikrit and a Sunni district of Baghdad.

In Najaf, a Shiite holy city where opposition to the former Sunni-dominated regime runs deep, dozens mocked the ousted ruler in a rally during which a man wearing a Saddam mask rode a horse through the streets alongside a police escort.

In other violence Friday:

– A roadside bomb killed an Iraqi policeman and wounded two in southwestern Baghdad, police said.

– Police found the corpses of two middle-aged Iraqi men in a mostly Sunni Arab neighborhood of western Baghdad. Two other bodies were found in Kut, police said.

– An Iraqi soldier was killed in Ramadi, where American soldiers exchanged gunfire with insurgents, U.S. officials said. No U.S. casualties were reported.

Associated Press writer Lee Keath in Cairo and Katherine Shrader in Washington contributed to this report.

AP-ES-04-28-06 2124EDT