A man was 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 (5) and son (10) after 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 police source said: "We believe the man was looking after the children for the first time since he divorced his wife."
Officers were unable to confirm reports that a knife was recovered from the murder scene.
Stevenson – who was said to be unemployed – had been living in France for some time, possibly around 10 years.
According to local reports, he and his former wife, an assistant accountant, had gone through a bitter divorce in the past couple of years.
She was awarded custody of the children following their separation and moved to live in Isere, a region to the south-east of Lyon, while he continued to live in the flat in the four-storey building.
Ahmed Benguedda, a former neighbour of the family, said that his seven-year-old daughter used to play with the two young victims, whom he described as "well adjusted".
"The people who live here are all in a state of shock," he told a Parisien newspaper.
Stevenson is expected to appear before a judge in Lyon today – a public holiday in France – for a short hearing, when a prosecutor will officially open an investigation.