A man wearing a white hockey mask forced his way into a Benton Avenue home Thursday night and demanded money from the resident.

According to Mark Lerum, Helena Police Department assistant chief, the resident was letting her dog in the back door when the incident occurred.

When the man demanded money, the victim told him she didn't have any. The man hit her on the head, ran through the residence and fled out the front door, Lerum said.

Lerum said the woman briefly called family members, then called police at about 9:15 p.m.

The police responded immediately, he said, and set up a perimeter of at least two blocks in each direction from the house, which is in the area near the City-County Building.

Officers used police dogs to try to pick up the man's trail, Lerum said, but were unsuccessful.

Lerum said the victim could not provide any description other than that the man was wearing the mask.

Anyone having information about the incident can call Crime Stoppers anonymously at 443-2000 or submit an anonymous tip through the Helena Police Web site at www.ci.helena.mt.us.

City Editor Richard Myers: 447-4071 or rich.myers@helenair.com