German authorities on Saturday arrested a suspect in the attempted bombing last month of two regional trains, federal prosecutors said. The man was believed to be one of two seen in a video recording from Cologne's main station on July 31, prosecutors said. Both trains passed through the station before the suitcase bombs, made with gas canisters, were found. In a statement, prosecutors gave no further details on the suspect, who was arrested early Saturday at the main station in the Baltic Sea port city of Kiel. Police closed off the station during their operation to ensure there was no "danger to the public," they said.