The double killing took place late on Friday night in the town of Völkingen in the southern German state of Saarland. The nine- and 10-year-old sons of the woman are said to have witnessed the shootings. They ran for help to their neighbours, who called the police.
Upon his arrest the man admitted immediately that he had shot the 49-year-old woman and her boyfriend, police said. Officers found a shotgun in his apartment, which is upstairs in the same building.
The exact motive is unclear but a police spokesperson said that long-standing quarrels about the rent between the landlord and his tenant may have been behind the incident.
The authorities are now seeking the children’s father who is thought to live in France.