Panic buttons could be installed on public transport across the UK in response to a rising number of sexual attacks on women.
Transport minister Claire Perry was discussing installing panic buttons on trains at a seminar on Women's Safety on Transport. More conventional measures to improve safety on public transport include an increase in CCTV and more police patrols on trains.
A total of 576 sexual assaults on trains including London Underground were reported in 2013, compared to 472 in 2009, meaning the number of incidents has gone up by a fifth.
Panic buttons would use GPS technology to give police the power to track the location of trains and board services at the next station. The move would mirror a trial which has taken place in India, where a number of high profile incidents of rape crimes have caused public outcry.
Perry said: "Investment in transport is at the heart of the government's long-term economic plan, and that includes making it safe for everyone to use.
"I am determined to do everything I can to make transport safer for women. That's why my department, along with British Transport Police (BTP), has funded a research project to find out what measures work on the ground, both here in the UK and internationally."
Improving safety for passengers will be included in all new franchises awarded to rail operators.