Site of explosion in central Lyon
Site of explosion in central LyonReuters

French police on Monday arrested a 24-year-old Algerian computer student suspected of planting a bomb in Lyon last week that wounded 13 people, authorities said, according to Reuters.

Three other people were also arrested in connection with the case, which is being treated as a terrorism investigation.

A man was spotted by security cameras leaving the explosive device, with screws and metal balls packed into a paper bag, in a pedestrian shopping street in the central French city on Friday a minute before it exploded.

Sources close to the investigation said the Algerian student, who is the main suspect, did not have police records, while the other three detainees included his mother and younger brother who is a high-school student.

Police found the man thanks to security camera footage, Lyon mayor Gerard Collomb told the local BFM TV.

France has been hit by a wave of terrorist attacks in recent years, beginning with the 2015 attack on the offices of the Charlie Hebdo satirical magazine which was followed by the attack on the Hyper Cacher kosher supermarket in which four people were murdered.

The Islamic State (ISIS) has claimed some of the attacks on France in recent years. The biggest of these attacks was the November 2015 Paris attack in which 129 people were murdered.

The country has been under a heightened alert in recent years in the wake of the attacks.