Aug 26 (Reuters) - A man was arrested after he stripped down to his boxer shorts, scaled a fence and rammed a pickup truck into a Southwest airplane parked at Eppley Airfield in Omaha, Nebraska, on Thursday, police said.

Two crew members suffered minor injuries on the Southwest Airlines flight, bound for Denver, as passengers were boarding at 9:30 p.m. local time (0230 GMT) when the man drove the truck into the plane's nose gear, said Omaha Airport Authority Chief of Police.

One of the 18 passengers on board the flight was also injured in the incident, the airline said in a statement.

The unidentified man was taken into custody and there was no suggestion the incident was an act of extremism, Connahan said.

He said airport security personnel had noticed a man "acting in a bizarre manner" near the perimeter of the airport. The man then stripped down to his boxer shorts, climbed over a fence and ran onto an airport runway as officers gave chase.

The man then jumped into a parked truck, which had its engine running, and drove it into the nose gear of the plane he was apprehended by police, Connahan said.

(Reporting by Brendan O'Brien in Milwaukee; Editing by Paul Tait)