PLYMOUTH (AP) -- Hennepin County authorities are searching for 31-year-old man on Medicine Lake.

According to the county sheriff's office, Paul Lindsen Myklebust was last seen about 2 a.m. Saturday, when he left a party to go on the Plymouth lake.

Reports say a boater called 911 at about 7:45 a.m. alerting them to an overturned kayak on the northwest side of the lake.

A jacket was found floating nearby.

The Hennepin County Water Patrol is helping the search with boats, the Minnesota State Patrol is searching by helicopter and divers are using sonar imaging equipment.

About 40 to 50 people are searching the area, including some of Myklebust's friends.

Police, fire and crime lab officials are also helping.