Three French police officers were shot dead when a man opened fire as they arrived at a house in a remote village in response to a call about domestic violence against a woman, police and French media say.
A search was underway for the suspected gunman and police reinforcements had been despatched to seal off the area, the interior ministry said. France's BFMTV broadcaster reported the suspect was still armed.
"Everything is being done to apprehend the individual and protect the population in the area," the ministry said in a statement.
French officials made no mention of any suspected militant motive behind the incident.
The incident began when a group of officers from the gendarme police force arrived at a house in a small hamlet near the town of Saint-Just in the early hours of the morning, following a call about domestic violence.
When police arrived, a man starting shooting at them and then set fire to the house, according to BFMTV.
The woman, who was the reported victim of domestic violence, sought refuge on the roof of the house and was rescued safely by police. The house was destroyed by the fire, BFMTV reported.
"This is a gendarme operation which is related to domestic violence, which has seen some developments that are still in progress," a representative of the regional prefect's office told Reuters.
The interior ministry said the three gendarme officers killed in the incident were aged 21, 37, and 45. A fourth officer, who was wounded, did not have life-threatening injuries, the ministry added in a statement.
Interior Minister Gerald Darmanin paid tribute to the officers who were killed.
"The nation bows down before their courage and commitment," he wrote on Twitter. "Everything is being done to find the person responsible for these acts."
-Reuters