Most of the casualties consist of civilians and "criminal elements attacked by us," said Tahseen al-Sheikhly, a spokesman for the Baghdad security crackdown called Operation Enforcing the Law.

Civilians are being caught in the crossfire because militants "use the population to cover themselves," al-Sheikhly said.

The number of Iraqi civilians killed and wounded nationwide continued to increase during April, with 969 killed and 1,750 wounded compared to the corresponding figures of 923 and 1,358 in March, according to Iraq’s Interior Ministry.

Three US soldiers in Iraq were killed Wednesday in two roadside bombings, the US military said. The first incident occurred at about 1am during a walking patrol in northern Baghdad. The other two died about 4:50 p.m. when an improvised explosive device detonated in southern Baghdad.

Another US soldier died on Wednesday in a bombing in the northern Iraqi province of Ninevah, according to the military.

The deaths bring the April death toll for the US military to 50, the highest monthly tally since September. Most of the deaths occurred in and around Baghdad, and most were combat-related.