TOKYO, Feb. 3 (UPI) -- Police in Japan are investigating a series of thefts involving more then 400 hand straps taken from public commuter trains.
The reports date back to November when 200 straps were stolen, no passengers have reported witnessing these thefts but police say all the straps were removed along with their belts which indicates the use of some kind of tool.
The most recent theft occurred on the Seibu Ikebukuro Line on Saturday night when the operator reported 16 missing straps across two cars.
"I have no idea what this person is going to use them for, but it causes trouble for our customers so I hope this person will stop doing this," a spokesperson from the Seibu Group told The Japan Times.
Police believe the thief may be attempting to sell the handles online, as a rail operator was able to sell 500 old straps for $15-$30 each.
But journalist Jun Umehara believes it may simply be an act of mischief.
"The straps aren't anything you could gain a huge profit by reselling them, so I believe it is either a prank or this person just wanted to make some noise," Umehara said.
Thefts have occurred on various different train lines throughout Japan and railway companies have begun to increase security in hopes of preventing these incidents.