MILAN, Italy (AP) — A tram derailed Friday and slammed into a building in the heart of Milan, killing two people and injuring more than two-dozen others, officials said.

The incident, along the central Vittorio Veneto avenue, came as the Italian business capital is hosting its seasonal fashion shows and is in the interim between hosting the Winter Olympics and Paralympic Games.

The No. 9 tram runs through the heart of Italy’s financial capital. It was supposed to have continued straight along Vittorio Veneto and was going at a high speed. But it suddenly swerved at a switch track that is used by another tram line and went off its usual course, according to video of the crash broadcast by Sky TG24.

Milan Mayor Beppe Sala suggested human error was to blame, saying the driver had apparently failed to switch the tracks to keep the tram going straight. Sala described the driver as a seasoned employee who had only been on his shift for an hour. But he said he had skipped a prior stop before the crash occurred, and would be questioned from the hospital where he was being treated for his injuries.

Sala confirmed two people had been killed — one passenger on the tram and one on the street. He said none of the other injured was in life-threatening condition.

Dozens of ambulances, fire trucks and police cars responded to the crash, with crews escorting passengers in thermal blankets away from the scene.

ATM, the Milan public transport company, said it was cooperating with prosecutors “to precisely establish the cause and dynamic of the incident.”