Image via NPS A Minnesota park ranger didn't intend to lay down his life when he responded to a distress call of a trapped family. But rarely do heroes know when they're called. The park ranger died trying to save three people trapped on a lake Voyageurs National Park in Minnesota on Sunday,

Flags are flying at half-staff in Minnesota and at national parks across the country for a Voyageurs National Park ranger who died trying to rescue a family of three.

The ranger - 55-year-old Kevin Grossheim - had a family of three in his boat and was towing their craft to the mainland in brutal conditions when they capsized.