French police have arrested a 24-year-old Algerian computer student suspected of planting a bomb in Lyon last week.
Authorities said Monday the blast wounded 13 people, in what is being treated as a terrorism investigation.
Three other people were also arrested in connection with the case.
A man was spotted by security cameras leaving the explosive device in front of a bakery's doorway.
It was loaded with screws and metal balls packed into a paper bag.