A woman and her three-year-old son were struck by a train and killed during the morning rush hour on Friday.

Donna Oettinger, 41, and her son, Zachary, died instantly when the 7.38am Uckfield to London Bridge service hit them as it sped through Riddlesdown rail station near Purley, Surrey. Witnesses reported seeing the pair walk on to the tracks at the suburban station before being hit.

Ambulance teams and Metropolitan police officers attended, but Oettinger and her son were declared dead at the scene.

British Transport police (BTP), who have launched an investigation, were called to the incident just before 8.30am. Police refused to comment on reports that the woman stepped off the platform, dragging the child with her, and lay down in the path of the oncoming train, but they do not believe anyone else was involved.

Commuter Paul Camlett arrived at the station just before 8.30am. He said: "The station master rounded everyone up and ordered them off the platform. Everyone was oblivious to what had happened. A woman screamed 'There's a body on the track!'

"I'm in complete shock. People were crying. They were in complete shock. The woman who screamed just could not speak."

Passengers on the train were eventually allowed to leave their carriages at 10am, more than 90 minutes after the incident.

Electrical power to the line between Woldingham and South Croydon was turned off and no trains ran on the line for several hours.

A BTP spokeswoman said: "I can confirm that the woman and child who died at Riddlesdown rail station on Friday 22 March have been named as Donna Oettinger, 41, and her son, three-year-old Zachary.

"BTP officers were called to the station after a report that a woman and a child had been struck by a train. The incident was reported to BTP at 8.29am and was also attended by Metropolitan police officers."

The station was temporarily closed while the emergency services dealt with the incident and the police investigation got under way. The train, thought to have been travelling at around 60mph, was not due to stop at Riddlesdown.

The senior investigating officer, Detective Chief Inspector Iain Miller, said: "Our thoughts remain with Donna and Zachary's family and friends at this sad and difficult time.

" Officers are continuing to work to establish the full circumstances of what happened, although early indications show that no one else was believed to have been involved. A file will be prepared for the coroner."

A spokeswoman for London ambulance service said: "We were called at 8.30am this morning to reports of two people under a train at Riddlesdown station. We sent a responder team in a car, an ambulance crew and officers. Sadly a woman and child were pronounced dead at the scene."