French investigators say they now know what happened to British student Isabel Peake, after reconstructing the moments leading up to her death.

Police and stunt co-ordinators have re-staged Ms Peake's fall from a train, on the main Toulouse-Paris line at Chabenet, near Chateauroux in central France.

They threw a dummy of the same size and weight as the 20-year-old Birmingham University student, and wearing the same clothes, from a train as it passed Chabenet at about 125kph (80mph).

They repeated the exercise four times, from four different positions, in attempts to determine whether Ms Peake fell, jumped or was pushed.

Colonel Bruno Hemar, part of the Chateauroux based inquiry team, said: "We are trying to recreate the exact conditions of the night the student was travelling, the fall, and especially how she came to be unclothed."

It was near the station at Chabenet that the badly injured body of the 20-year-old was found on 13 October last year.

Her body was found to be naked up to the waist, although forensic scientists found no evidence that she had been raped.

Police had also not been certain whether Ms Peake was the victim of an accident, or of one or more assailants.

During the reconstruction, a man succeeded in pushing the dummies out of the train without assistance. Two were pushed through a window, two from a carriage door.

Police also needed to know what effect the fall would have had on Ms Peake's clothes.

The first dummy had its head torn off by the fall. The damage to the others was also severe, the limbs dislocated and the clothing torn to shreds.

After the reconstructions, the two examining magistrates, Michel Bonnieu and Jean Dematteis, expressed their "very great satisfaction" with the information gained from them.

"We now know what happened," Mr Dematteis said, without elaborating.

The prosecutor at Chateauroux, Christian Ponsard, said that as the day progressed, the theory of an accident became increasingly improbable.

However, he told a news conference that it was too early to make public the investigators' opinions about what happened to Ms Peake.

"There are still many theories that we have but we will have more or less convincing evidence and there will be some theories that are more convincing than others," he said.

Investigators will be studying taped video evidence from five cameras placed at the trackside, which filmed the reconstructions.

Two British officers flew out from Birmingham on Friday to oversee the reconstruction, although they are not officially involved in the inquiry.

French police have been broadly criticised for the inquiry into Ms Peake's death, accused of a series of blunders and a failure to address the seriousness of the crime early enough.

Journalists in France expressed surprise at the scale of the high-profile reconstruction - a rare event in France - and said it was being staged for the benefit of the British media.

But Mr Ponsard said: "I don't think that since the start of the investigation we have bowed to media pressure. We have taken our time and acted in our own time until the time was right to act.

"This reconstruction had been planned for a long time...we needed to coordinate with the SNCF (the French rail operator) and other organisations. These things are not sorted out overnight," he said.

French authorities are currently waiting to speak to a 20-year-old Marseilles man who was said by witnesses to have chatted to Ms Peake in Limoges shortly before she boarded the train.

Sid Ahmed Rezala has been remanded in custody in the Portuguese capital Lisbon, pending extradition proceedings to France.

He is also wanted for questioning by police in Dijon about the murder of a mother-of-two on a sleeper train, and in Amiens over the death of a female student friend who was found in a coal cellar at his rented accommodation.