A British father is due to appear in court in France today, where he is expected to be formally charged with slitting the throats of his two young children.
Julian Stevenson, 47, is alleged to have killed his daughter, five, and son, 10.
He was entrusted with them for the first time since separating from his French wife.
It is thought she discovered the bloody scene when she arrived at his flat on Saturday afternoon and found her former husband standing on the stairway in blood-stained clothes
Reports suggested she had gone to his home, in Saint-Priest, to the south-east of Lyon, after he failed to return the children following the visit.
Stevenson was held after witnesses reportedly spotted him fleeing the area on roller skates and taken into custody on Saturday evening.
A British father has admitted slitting the throats of his two young children in France following a difficult divorce, sources said.
It is understood that the man, who has not yet been named, was recently divorced and was looking after his children for the first time since separating from his wife.
ITV News Correspondent Harry Smith reports:
A British father being question in France on suspicion of slitting the throats of his two children had reportedly been living in France for 10 years.
It is thought that his French wife came to pick up the little girl and her older brother when he failed to return the children yesterday, following their visit.
According to reports, a knife was recovered from the murder scene.
The Foreign Office is investigating reports that a British man has been arrested on suspicion of slitting the throats of his two children in France.
The bodies of the children, said to be aged five and 10, were discovered in a flat near Lyon yesterday afternoon, according to local reports.
We understand that a British national has been arrested in France. We’re in contact with the French authorities and await the outcome of their investigation. We stand ready to provide consular assistance.
A 48-year-old British man has admitted to killing his two young children by slitting their throats in the central French city of Lyon, prosecutors told Agence France Press agency.
The divorced and unemployed father confessed that he had slain his five-year-old daughter and 10-year-old son "but did not go into details of the motive," they said.
A British father is being questioned in France on suspicion of slitting the throats of his two children, local police said.
The man who has not been named, was taken into custody yesterday evening following a manhunt.
A police source said: "We believe the man was looking after the children for the first time since he divorced his wife.
"He was arrested at the end of yesterday afternoon".
The mother, an assistant accountant, had won custody of the children following her divorce and had left to live in Isere, a region to the south-east of Lyon, while the unemployed father continued to live in the flat, according to the Parisien paper.
– Ahmed Benguedda, a former neighbour of the family
The people who live here are all in a state of shock.
French news reports claimed the 48-year-old man was arrested after his former wife spotted him on the stairs to his flat with blood-stained clothes. Several witnesses reportedly spotted the man fleeing the scene, in Saint-Priest, a suburb to the south-east of Lyon, on roller skates.
He and his ex-wife were said to have recently gone through a difficult divorce. The father was reportedly taken into custody following a manhunt yesterday evening.