Freiburg, typically a tranquil town in Germany's Black Forest, has seen two mysterious deaths this week that have left police scrambling for answers, authorities reported on Thursday. The town's police department said they were searching for a group of four men who beat a 51-year-old so severely he died of internal bleeding.

In a statement to the press, Freiburg police said that the man's son called them to relate the story of how his father was insulted and then beaten by three men in their 30s, and one in his 50s, as he went to relieve himself behind the church of St. Johann. He declined to go to the hospital, and died several hours later, likely of injuries sustained from the beating. 

He said that his father had been attacked in broad daylight, between 3 and 4 p.m. on October 12, right in the heart of Freiburg's busy downtown and a stone's throw from a key local government building. He had complained of pains in his upper body to his son, but did not seek medical or police attention; the son approached police on October 15.

"The family is in complete shock," said police spokeswoman Laura Riske, according to the local Badische Zeitung newspaper.

A few days later, a dead woman was found floating in the Dreisam river by a jogger near the city's football stadium. Police later established that she was about 19 years old, and had drowned after a "violent attack," the nature of which the coroner could not yet establish. As of Friday, police were still trying to pin down her identity, having little evidence other than an abandoned white bicycle, even after receiving hundreds of tips.

Freiburg is typically known for its university and reputation as the "green" city of Germany.