A police officer shot and wounded a man who attacked a group of three officers with a hammer near Notre Dame Cathedral on Tuesday, authorities said.
Interior Minister Gerard Collomb told reporters that the man yelled "this is for Syria" when he attacked the officers.
Collomb said that an officer used his weapon to shoot the assailant.
The man was also armed with kitchen knives, Collomb said.
Paris police tweeted that one officer was wounded in the attack.
CBS Radio News' Elaine Cobbe reports that the investigation has been handed over to the police's anti-terrorism unit, but the police also said there was no confirmation at this stage whether the incident was a terror attack.
UPDATE: Paris officials say policeman was attacked by a man with a hammer.— CBS Evening News (@CBSEveningNews) June 6, 2017
Suspect was shot. Attacker is alive & taken to the hospital. pic.twitter.com/HaAqEJiHbN
The incident happened around 4:30 p.m. A large number of police cars filled the area on the Ile de Cite island in the Seine River in the center of Paris.
Hundreds of people on the esplanade in front of Notre Dame were evacuated and authorities urged people to stay away from the area. People inside Notre Dame, the nearby Sainte-Chappelle cathedral and area bars and cafes were told to stay inside.
Mikey Kay, a retired wing commander for the British military, reported on CBSN that police sealed off a bridge to motor traffic near the cathedral, but it was open to pedestrian traffic.
Witnesses described a dramatic police operation in the tourist-filled area.
Lawrence Langner, a 73-year-old American visiting the neighborhood just across the Seine River from the cathedral, told The Associated Press that he suddenly heard a commotion and two detonations like gunshots.
Journalist David Metreau, who said his office overlooks the square that fronts Notre Dame, tweeted that there were two blasts that sounded like shots. Looking down from his office, he saw a man inert on the square.
"The police didn't seem interested in him at the beginning," Metreau said. "I thought he was dead."
They then checked his pulse and medics later came and took him away on a stretcher.
Others posted photos online of what appeared to be the interior of medieval Notre Dame, one of France's most-visited monuments.
Police spokeswoman Johanna Primevert told The Associated Press just before 5:30 p.m. that the operation was over. She did not provide further details.
Paris remains under high security after a string of Islamic extremist attacks in recent years, including several targeting police officers and security personnel.
In April, an attacker opened fire on a police van on Paris' Champs Elysees, killing one and gravely wounding two others. The attacker was shot dead by police.
The incident recalled two other attacks on soldiers providing security at prominent locations around Paris, one at the Louvre museum in February and one at Orly airport in March.