DRESBACH, (AP) - One person is missing after a tugboat went over the roller gates near the Dresbach dam in eastern Minnesota.

Three people were aboard and two made it to safety. They were being treated for minor injuries.

The Winona County Sheriff's Department received a 911 call at 6:15 a.m. Wednesday that a tugboat had gone through the roller gates at Lock and Dam No. 7.

Winona County Chief Deputy Ron Ganrude says they are still trying to determine what happened that put them in that situation.

The dam is the same place where 11 people were rescued after a rented houseboat was swept over the roller gates and capsized May 27.

In 2007, four drowned at the dam when their boat was sucked back into the dam.