Authorities say a rail dispatcher in southern Germany was using his cellphone to play games shortly before two trains he was in charge of collided head on in February, killing 11 people.
Prosecutors in Traunstein, east of Munich, say the unnamed dispatcher was arrested Tuesday on suspicion of negligent homicide.
In a statement, prosecutors said the man was likely distracted from his work, leading him to give the trains the wrong signals. He then made a mistake sending an emergency message, which the train drivers couldn't hear.
Prosecutors said the man admitted playing games on his phone, but denied having been distracted.
The two commuter trains collided on a single-track line near Bad Aibling on Feb. 9.