Four U.S. soldiers were killed in separate attacks in Baghdad and north of the Iraqi capital, the military said Wednesday.

Two soldiers died Tuesday in an explosion in Diyala province, the U.S. military said in a statement. Four other soldiers were wounded in the blast and evacuated to a U.S. combat hospital, it said. Diyala is a dangerous area known to have a strong al-Qaida in Iraq presence, northeast of Baghdad.

Another soldier was killed and five others wounded by an explosively formed penetrator, or EFP, Wednesday in central Baghdad, the military said in another statement. An Iraqi civilian was killed and two others were also wounded in the blast, it said.

EFPs fire a slug of molten metal capable of penetrating even the most heavily armored vehicles, and are have been responsible for hundreds of U.S. deaths in Iraq.

A fourth soldier was mortally wounded by gunfire Wednesday while providing security during a training mission for Iraqi police near Mosul, 360 kilometers (225 miles) northwest of Baghdad, the military said in another statement.

The victims' names were withheld pending family notification.