Swiss police have said that a 32-year-old Iranian asylum-seeker was killed by police after he used an axe and a knife to seize more than a dozen hostages for several hours on a train in western Switzerland. No passengers were injured.

The man took the hostages early Thursday evening and police, alerted by passengers, sealed off the area while the train was stopped in the town of Essert-sous-Champvent, police in the French-speaking Vaud region said on Friday.

The man, speaking Farsi and English, demanded that the train engineer join the 15 hostages.

Almost four hours after the incident began, police stormed the train after trying to negotiate with the man through an interpreter. More than 60 officers were involved.

“The hostages were all freed safe and sound,” a police statement said. “The hostage-taker was mortally injured during the operation.”

Vincent Derouand, a spokesman for the Vaud prosecutors’ office, said an investigation was underway in part to determine the man’s motive.