BAGHDAD, Iraq (AP) – Bombings struck four coalition and Iraqi military convoys and a provincial government office Monday, killing at least eight people, including an American soldier and an Estonian trooper in the Baghdad area.

Coming a day after the bodies of nearly 50 Iraqi military recruits were found massacred, the bombings occurred as a U.N. agency confirmed that several hundred tons of explosives were missing from a former Iraqi military depot in an insurgent hotspot south of Baghdad.

The revelation raised concerns the explosives fell into the hands of insurgents who have staged a spate of bloody car bombings, although there was no evidence to link the missing explosives directly to the attacks.

On Monday, a roadside bomb in western Baghdad killed one U.S. soldier and wounded five, the U.S. military said.

An Estonian soldier died when a roadside bomb exploded at a market just outside Baghdad as his patrol went by, the Estonian military said. Five other Estonian soldiers were wounded.

A car bomb also targeted an Australian military convoy 350 yards from their country’s embassy in Baghdad, killing three Iraqi civilians and wounding nine people, including three Australian soldiers who suffered minor injuries, Iraqi and coalition officials said.

“This is the first time that … Australian vehicles have been attacked by direct enemy action,” an Australian Defense Force spokesman, Brig. Mike Hannan, said in Australia’s capital, Canberra.

Two Islamic groups posted Web site claims of responsibility for the attack on the Australians. One was posted in the name of Jordanian militant Abu Musab al-Zarqawi’s group, renamed Al-Qaida in Iraq.

The other claim was made on behalf of the Islamic Army of Iraq. It was impossible to determine if either claim was genuine.

Al-Zarqawi’s group, formerly known as Tawhid and Jihad, has been blamed in numerous suicide car bombings and beheadings of foreign hostages, including deadly twin bombings inside Baghdad’s highly secured Green Zone, which houses the U.S. and Iraqi leadership.

The Islamic Army of Iraq has claimed responsibility for the August abduction of French journalists Christian Chesnot, 37, and George Malbrunot, and other kidnappings.

In near-simultaneous attacks Monday in the northern city of Mosul, suicide car bombers struck provincial government offices and a military convoy, the U.S. military said. Three government employees were killed and one injured at the offices and an Iraqi general was slightly injured in the attack on the convoy, a government spokesman said.

Insurgent attacks across Iraq have increased by 25 percent since the holy month of Ramadan began two weeks ago. Attacks on U.S. and coalition forces averaged 56 a day last month – down from a high of 87 in August.

On Monday, the International Atomic Energy Agency said 377 tons of conventional explosives suitable for car bomb attacks had vanished from a former Iraqi military installation about 30 miles south of the capital.

The agency based in Vienna, Austria, said it had been informed on Oct. 10 by Iraq’s Ministry of Science and Technology that the explosives were missing from the former Al-Qaqaa facility south of Baghdad.

Al-Qaqaa is near Youssifiyah, an area rife with ambush attacks.

An Associated Press Television News crew that drove past the compound Monday saw no visible security at the gates of the site, a jumble of low-slung, yellow-colored storage buildings that appeared deserted.