Iraqi police were ambushed Tuesday night in western Baghdad as raiding a house where they suspected militants were sheltered and 28 people were killed, including seven policemen, police said Wednesday.

A powerful explosion tore through the house as the police broke in, the police said.

A police official said the attack was "evidently an ambush" and the insurgents used "massive amounts of explosives."

Police said they received an anonymous call informing them of the suspected insurgent hideout in the Ghazaliya neighborhood.

The powerful explosion also damaged several buildings nearby, and several people are being trapped under the rubbles.

Police have regularly been targets of insurgents in Iraq. And attacks by insurgents are expected to escalate further as the Jan. 30 general election in Iraq is drawing near.

Source: Xinhua