LEGANES, Spain (Reuters):

Three men sought for the Madrid train bombings and a police officer were killed when the suspects set off an explosion when cornered on Saturday, the government said.

"Right now I can tell you that there are three bodies of suspected terrorists who may have killed themselves," Interior Minister Angel Acebes told a news conference.

A police officer was killed and 11 others injured during the operation in the southwestern Madrid suburb of Leganes, Acebes said.

Police units arrived at a Leganes flat on Saturday evening in search of suspects in the March 11 bombings that killed 191 people, Acebes said.

When the occupants of the flat spotted the police, "they began firing and shouting and chanting in Arabic," he said.

The police were about to raid the flat when the suspects set off a powerful explosion, he said.