BEIJING — A fire that tore through a karaoke bar in southern China in the early hours of Tuesday killed 18 people, the police said, and a man was arrested on suspicion of arson hours later.

A brief initial police account of the blaze in Qingyuan, a city in Guangdong Province, said firefighters received an emergency call about 30 minutes past midnight.

By the time they extinguished the fire about 25 minutes later, the karaoke bar was gutted. In addition to the 18 dead, the police said, five people rescued from the fire were hospitalized.

“According to a preliminary investigation, the blaze was arson,” the online statement from the Qingyuan police said. “Currently, the public security authorities are stepping up their investigation.”