The bodies of three people were found in the German village of Weitefeld, about 60 km east of Bonn, and it is assumed that their cause of death was a criminal offense, DPA reported, citing police.
Law enforcement agencies have urged drivers in the region not to pick up anyone hitchhiking in their cars while they search for the possible attackers, BTA reports.
A large number of police officers have been sent to the site where the bodies were found.
A police spokesman declined to give further details, saying only that the crime was committed early this morning.