A 38-year-old drug user was seized after a gruesome severed human head was found outside a court building.

Shocked passers-by in Bonn, Germany, called police after spotting the head outside the city’s district court at 5.40pm on 28th June.

The rest of the corpse was reportedly found on the banks of the river Rhine near Alter Zoll, around one kilometre (0.6 miles) away.

Police arrested a 38-year-old man sitting just a few metres from the head.

These images show how police sealed off the crime scene with tarpaulin. Officers also blocked the street to vehicles and pedestrians.

The victim was a 44-year-old man, reported local media.

The suspect was already known to police, mainly because of drug-related crime, said investigators.

The nature of the relationship between the two men – or if they even knew each other – was still unclear at the time of reporting.

The murder weapon had not been found at the time of reporting, either.

Both men were homeless, according to initial findings.

The investigation is ongoing.