A major police operation was under way at the university’s Neuenheimer Feld campus, they added on Twitter, urging people to steer clear of the area “so that rescue workers and emergency services can travel freely”.

Police vehicles parked on the grounds of Heidelberg University after the shooting. Photo: picture alliance/dpa//Pr-Video | R.Priebe

German newspaper Bild said the shooter opened fire in the lecture hall and injured several people before turning his weapon on himself, Reuters reported.

Citing sources, German newswire DPA described the attack as a “rampage”.

The attack happened around 12 noon, according to police. The area has been cordoned off while investigations continue.

Broadcaster SWR reported that the university had contacted its students by email urging them to avoid the area.

Heidelberg is a picturesque university town in the state of Baden-Württemberg, home to a population of around 160,000 people.

The university’s Neuenheimer Feld campus, shown below in the map, hosts natural sciences departments, part of the university clinic as well as a botanical garden.

Strict gun laws

Germany has been hit in recent years by a spate of attacks, mostly perpetrated by jihadists or far-right militants.

School shootings however are relatively rare in Germany, a country with some of the strictest gun laws in Europe.

In 2009, a former pupil killed nine students, three teachers and three passers-by in a school shooting at Winnenden, also in Baden-Württemberg. The gunman then killed himself.

In 2002, a 19-year-old former student, apparently in revenge for having been expelled, gunned down 16 people including 12 teachers and two students at a school in the central German city of Erfurt. He too then killed himself.