In November, police released an image of a male motorcyclist they wanted to speak to in connection with the killings.
The French Gendarmerie released an artist's impression of a motorcyclist who was seen riding in the area shortly before the four murders took place.
The man's helmet was said by Mr Maillaud at the time to be "very particular" and one of only a few thousand models worldwide, with a bottom section which opened laterally to reveal the lower face.
Read more: Man arrested over Alps killings
More top news
Mr Trump said Kim Jong Un had not met unspecified “conditions” for the summit.
Lava has destroyed a building near the plant in Hawaii.
TV presenter Helen Skelton is a supporter of the campaign and is calling for more parents to get out on their bikes with their children.