Montana's governor has signed an executive order freeing up more resources for law enforcement officers as they search for a former U.S. soldier suspected in a deadly shooting at a Montana bar last week.

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

Four people were killed in the attack inside the Owl Bar in Anaconda, Mont. The authorities are still searching for the suspect, an Army veteran who lived nearby.