Southern rail
Commuters onboard a Gatwick Express (file photo)Jack Taylor/ Getty Images

An investigation is underway after reports that a couple had sex on the Gatwick Express train that runs from London Victoria Station to Gatwick Airport. The accused are alleged to have carried out a sex act while travelling on the 9pm service last Thursday.

The British Transport Police have not confirmed the nature of the act but say that the couple consisted of a man and a woman.

It is also not clear whether the frisky couple were departing or returning from a holiday, or whether they were on a business trip.

A spokesperson for the force told IBTimes UK: "We are appealing for witnesses to come forward after an allegation of a couple engaging in a sexual activity on a Gatwick Express train. The incident was reported to the BTP shortly before 9.30pm on Thursday, August 10."

The Gatwick Express is a regular service between London Victoria, Gatwick Airport, and Brighton. It is operated by Govia Thameslink who are also responsible for the troubled Southern network.

The service opened in May 1984 with air-conditioned carriages operated by British Rail. National Express took over the franchise when it was privatised in April 1996. In June 2008 it was merged into the Southern train operating company, although it continues to be maintained as a separate identity. In July 2015, Southern including the Gatwick Express service was merged into Govia Thameslink Railway.