Parts of a national forest near Anaconda, Montana, were closed late Saturday as authorities expanded their search for the gunman accused of killing four people at a bar on Friday morning.

The search for Michael Paul Brown, the suspect in the deaths of a bartender and three patrons at Owl Bar, continued into the weekend. Authorities have warned that he is armed and dangerous.

Hundreds of law-enforcement officers have combed through western Montana by air and land for the suspect, and authorities are offering a $7,500 reward for information leading to him.