East Japan Railway Co. plans to install security cameras in trains on the Saikyo Line linking Tokyo and Saitama Prefecture in a bid to prevent groping, becoming the nation's first railway to take such a step for commuter trains, company officials said Dec. 12.

A set of high-definition security cameras will be installed in the No. 1 cars of Saikyo Line trains, such as in the ceiling and the overhead rack, on a trial basis by the end of this year at the earliest, they said. Most groping cases have been in the No. 1 cars of trains.

JR East and police say they hope the security cameras will provide "evidence," and serve as "deterrence" against molestation. But critics questioned the effectiveness of the cameras, voiced concerns about privacy and said they may be used for other criminal investigations.

JR East will consider installing security cameras in other Saikyo Line train cars or in trains serving other lines after seeing how the trial goes, the officials said.