Police are seeking clues to how a 23-year-old man ended up alone with a bleeding head injury in a snow-covered ditch along a main road through Fridley early Saturday.

A motorist's headlights spotted the man about 3 a.m. on the east side of the 7300 block of Hwy. 65, according to police. The man had suffered blunt-force trauma to the head and was lying along a stretch of the four-lane highway that is dotted with gas stations, trailer parks and a self-storage business. Investigators don't know how the man received the head injury.

"We've got a lot of questions how he got there," said Gary Patterson, a detective working the case for the Anoka County Sheriff's Office. "It's not real clear how this occurred."

The man was in critical condition at Hennepin County Medical Center on Saturday. His identity has not been released. Investigators are asking anyone with information in the case to call 763-427-1212.

BRAD SCHRADE