In Japan, where train travel can often be a perilous ordeal for women, an insurance company is reporting a sudden run on a policy that protects men falsely accused of groping.

The spike in takers for the 6,400 yen (US$57) "false groping accusation benefit" plan was triggered by a spate of incidents where men suspected of molesting female commuters fled the scene along the railway tracks, the Tokyo-based firm told AFP.

Japan has made efforts to tackle the problem of rush-hour sex pests with posters on trains and television campaigns, while railway operators provide women-only carriages for the busiest times of day. But the plan, devised by the Small Amount and Short Term Insurance company in 2015, covers legal costs for policy-holders who find themselves on the wrong end of such a charge. It was initially set up as a fringe benefit under which fees for any legal consultation, including domestic or traffic accidents, were covered, Japan's Mainichi newspaper reported.

But the firm's helpline service - which alerts lawyers practising in the vicinity of the alleged groping incident - has proved a hit with customers.