Paris, Nov 1 (IANS): A Greek Orthodox priest was seriously injured in a shooting outside a church in the French city of Lyon, authorities said, adding that a search operation was underway to nab the suspect who is on the run.

The incident took place at about 4 p.m. (local time) on Saturday evening when the priest, identitied as Nikolas Kakavelakis, was closing the church, the BBC reported citing officials as saying.

While the motive for the shooting was yet to be ascertained, the authorities have launched a probe for attempted murder.

Police said the attacker was armed with a sawn-off shotgun.

While the perpetrator managed to escape, "a person who could correspond to the description given by the initial witnesses has been placed in police custody", Lyon's public prosecutor Nicolas Jacquet told the media on Saturday night.

Meanwhile, Kakavelakis has been hospitalised with life-threatening injuries and is said to be critical condition.

Calling the incident an "Islamist terrorist attack", President Emmanuel Macron said that thousands of extra soldiers have been deployed to protect public sites, including places of worship, the BBC reported.

In a statement, Prime Minister Jean Castex said the government was determined to allow "each and everyone to practice their worship in complete safety and in complete freedom".

Saturday's shooting came three days after the 21-year-old Tunisian man Brahim Aouissaoui stabbed three people to death inside the Notre-Dame basilica in the city of Nice.

In another gruesome attack on October 16, middle-school teacher Samuel Paty was beheaded by an 18-year-old Muslim immigrant, Abdullakh Anzorov inside a school near Paris.

France has raised its national security alert to the highest level.