Rep. Leonard Boswell, D-Iowa, and his family were victims of a home invasion at their rural farmhouse over the weekend.

An intruder entered the home Saturday night through the front door, physically assaulted Boswell’s daughter, and demanded money at gunpoint, a statement from the congressman’s office said.

Hearing his daughter’s screams, the 77-year-old Boswell — who served two terms in Vietnam — tussled with the intruder to try to yank the weapon from him, the office said.

The incident ended when Boswell’s 22-year-old grandson grabbed a gun from another room and pointed it at the intruder — sending him running into the woods, said Jane Slusark, the congressman’s spokeswoman.

Other than a few scrapes and bruises, the eight-term congressman and his family were unharmed, Slusark said.

Local, state and federal authorities are investigating the incident.

Boswell represents Iowa’s 3rd District.

CNN’s Paul Courson contributed to this report.