A car rammed into a roadblock put up by protesting farmers in southwestern France on Tuesday, killing a woman and her teenage daughter, and seriously injuring her husband.
Farmers have been blocking roads across the country in protest at what they say are deteriorating conditions in the agriculture sector.
The three occupants of the car that crashed into the barrier on a motorway in the southwestern department of Ariege were taken into police custody on suspicion of involuntary manslaughter, police said.
The vehicle was travelling on the dual-lane carriageway leading to the roadblock despite it being clearly marked as closed to traffic because of the protest, Ariege prefect Simon Bertoux told reporters.
But a local prosecutor, Olivier Mouysset, said that early results of the investigation suggested that the car, carrying a couple and a friend, had not rammed the barrier intentionally.
In the dark, the car ran into a wall made of bales of straw at the roadblock, hit the three people and only came to a halt when it crashed into the trailer of a tractor, Mouysset said.
The 35-year-old woman who was killed was a member of the powerful FNSEA farmers union, which has been leading nationwide protests.
Her 14-year old daughter was taken to hospital where she later died. The wounded husband is 40.
A police source added that the car was travelling "at speed" as it drove into the barrier.
A test showed that the driver, a 44-year-old man, was not under the influence of alcohol or drugs.
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