The mental health of suspected Montana gunman Michael Paul Brown, 45, declined significantly following the death of his mother, relatives said.

Police are looking for Michael Paul Brown, 45, who's wanted for allegedly shooting four people in The Owl Bar in the small town of Anaconda, Montana.

The search for a former U.S. soldier suspected of killing four people at a bar in Montana stretched into a fourth day Monday, with deputies scouring the mountainous terrain by foot and air after the man escaped in a stolen vehicle containing camping gear.