Four people were injured in a gun attack at Heidelberg University in south-western Germany, security sources told dpa. One of the victims was in a life-threatening condition, they said. Heidelberg University, founded in 1386, is Germany’s oldest university and also one of Europe’s oldest. It has several campuses in the picturesque city of Heidelberg, with a population of some 160,000 people, on the Neckar river.