Three men with links to a French jihadist who murdered a police officer and his partner have been arrested after allegedly carrying out surveillance of other police officers.
Larossi Abballa murdered police commander Jean-Baptiste Salvaing and his partner Jessica Schneider at their home in Magnaville near Paris on 13 June.
Two of the alleged associates were arrested on Saturday, while the third was arrested Tuesday in the Paris suburbs of Mureaux and Mantes-la-Jolie, home of Abballa, who was shot dead by police after the murders.
One of the three arrested was on a terror watchlist. They are suspected of spying on police at a public event in the Yvelines region west of Paris, police sources told AFP.
"There was a chance that these people might carry out other attacks against police officers. We were removing any doubt," said the Versailles prosecutor leading the investigation.
Abballa, a French citizen of Moroccan origin, pledged allegiance to Islamic State, and after murdering the couple live streamed footage of himself with their three-year-old toddler on Facebook and pledged to turn the Euro 2016 football championships currently being hosted by France into a "graveyard."
The men arrested Saturday have been named as Charaf-Din Aberouz and Saad Rajraji, founding members of a banned group which sent extremists to Pakistan. They were jailed alongside Abballa in 2013 for their involvement with the group.
Authorities have not yet named the third man arrested.