“Thankfully no one has died,” the BTP tweeted shortly after 9:00 p.m. native time (5:00 p.m. EDT) Sunday.
Officers are persevering with to reply to the incident on the Fisherton Tunnel, the company added.
Earlier Sunday, BTP officers had been referred to as to help, “following reports a train derailed.”
A tweet from the Wiltshire Police additionally mentioned cops have been responding with fireplace and ambulance service “at the scene of a train crash involving two trains between Andover and Salisbury.”
An announcement from Network Rail Wessex mentioned the incident concerned the 17:08 p.m. Great Western Railway service between Portsmouth Harbour and Bristol Temple Meads and the 17:20 p.m. South Western Railway service from London Waterloo to Honiton.
The line stays closed as emergency companies perform their work, Network Rail Wessex added.