A man suspected of having shot dead a French policeman in the city of Avignon last week has been arrested, along with another individual, said French Interior Minister Gerald Darmanin on Twitter.
"This crime will not go unpunished," said Darmanin, as he congratulated the police for having made the arrests.
Eric Masson, 36, a father-of-two, was shot and killed Wednesday while investigating activity at a known drug-dealing site in the city.
Sunday's arrests came a few hours after several hundred people attended a ceremony in honor of the fallen officer at Avignon's police commissariat.
Darmanin and Prime Minister Jean Castex are due to attend a homage to Masson in the city on Tuesday.
The officer's death has caused deep shock in Avignon, a city better known for its summer theatre festival than for violent crime, and reignited a debate over President Emmanuel Macron's record on fighting crime.
Polls show that violent crime is a top concern of voters ahead of next year's presidential election, in which Macron is expected to seek a second term.
An Elabe poll last month found that 65 percent of voters were unhappy with the president's record on maintaining law and order.