BRUSSELS, Belgium — Police detained a man in eastern Belgium after a dinner guest found the bodies of the host’s wife and stepson in a freezer, authorities said yesterday.

The female guest opened the freezer while helping to clear upafter a dinner with a group of friends Tuesday at the man’s home in the city of Verviers, 78 miles east of Brussels, said Christine Wilwerth of the city prosecutor’s office.

“It was a lady who at the end of the meal at a friend’s house, and after washing the dishes … decided to take the leftovers of the meal down to the basement to store in the deep freeze,” Ms. Wilwerth said. “Once she opened the deep freeze, she discovered the bodies.” Guests alerted police, who identified the bodies of the man’s wife and her 12-year-old son. The bodies appeared to have been kept in the deep freeze for several weeks.

Ms. Wilwerth said the suspect acknowledged that a domestic quarrel had escalated and his wife had been stabbed, but she said he had not explained the circumstances of the child’s death.