At least 30 people were injured when two trams collided at Strasbourg Central Station on Saturday, authorities said.

Videos and photos posted on social media showed dozens of people inside two trams. A video showed smoke rising and chaos as the alarm sounded.

Local media reported that the accident occurred after one of the trams changed tracks and collided with a stationary tram. Other reports said a streetcar was reversing at the time.

A spokesman for the county said an investigation into the cause of the accident has been launched and it has not been confirmed whether anyone died.

Strasbourg Mayor Jeanne Barseghian told reporters at the scene that a tram had collided, but the cause was not yet clear.

Barseghian called on people to wait for the results of the investigation, BFM TV reported.

A witness named John told AFP he saw a tram reversing at high speed, adding: “We heard a huge crash, a loud bang.”

Another witness told BFM television that the tram’s door flew away on impact.

The outlet reported that a large security cordon was set up in front of the station.

The Lower Rhine region’s fire and rescue service posted a message on X urging people to avoid the area to allow emergency services to access the area.

Rene Sellier, the service’s director, said some of the non-fatal injuries reported were “mostly traumatic” but also included scalp wounds, collarbone fractures and knee sprains

“There are about 100 people who suffered no specific injuries but are being checked by doctors,” Sellier said.

He added that around 50 vehicles and 130 firefighters were sent to the scene and the situation “could be more serious”.

Emmanuel Auneau, director of CTS, which manages public transport in Strasbourg, said the two tram drivers were “not physically injured but were very shaken”.