The man arrested in France has a motorcycle helmet similar to one in an e-fit issued by police, according to a French broadcaster. BFM claimed the man lived alone in the mountains and was found with arms in his home.
In November, police released an image of a male motorcyclist they wanted to speak to in connection with the killings. at the time the helmet was said to be "very particular" and one of only a few thousand models worldwide.
More top news
The former head of the Diplomatic Service breaks down the hidden meanings behind Theresa May's letter to Donald Tusk
The storms that struck Texas and Oklahoma late on Tuesday brought tornadoes, tennis ball-sized hail and powerful winds.
Samantha Baldwin, 42, and her sons Louis Madge, nine, and Dylan Madge, six, haven't been seen for two days.