A 31-year-old woman, angered that her younger sister was romantically involved with her boyfriend, was arrested Tuesday after police said she punched her and struck her in the head with a brass lamp and paint can in their Brookside Drive home.

Courtney Longo was charged with second-degree assault, second-degree unlawful restraint and disorderly conduct.

Police were alerted to the incident by St. Vincent's Medical Center in Bridgeport, where a friend took the victim after she had fled from the home.

Longo assaulted her sister in two separate fights -- one on Monday night and the other Tuesday afternoon -- because she believed her sister was having an affair with Longo's boyfriend, according to the report. Longo also prevented the younger sibling from leaving the house by standing in the front door, police said.

The victim suffered a black eye, a bruise on the bridge of her nose, bruises on her forearms and shoulder, a lump and scratches on her forehead, cuts on the side of her head and her left hand, a bruised shin and a swollen middle finger, police said.

The younger sister "tried to hit Courtney in self defense, but was unable to," said Deputy Police Chief Christopher Lyddy.

Longo was released on a promise to appear Wednesday in Bridgeport Superior Court.