A soldier on Friday shot and wounded a man armed with a machete who was trying to enter the Louvre museum in central Paris, police said.
Police sources told the Reuters news agency that the man had been trying to get into the museum’s underground shop with a suitcase.
“We are dealing with an attack from an individual who was clearly aggressive and represented a direct threat, and whose comments lead us to believe that he wished to carry out a terrorist incident,” Michel Cadot, the head of the French capital’s police force, said, adding the man had shouted, “Allahu Akbar”.
“There was also a second individual who was behaving suspiciously, who has also been detained, but for now there does not appear to be a link between that individual and the attack,” Cadot said.
The interior ministry said on Twitter that the incident was “serious”.
Al Jazeera’s Natacha Butler, reporting from Paris, said the motivation of the attacker was unknown.
“We cannot confirm if the attack is over yet, but we know the attacker has been severely wounded and the entire area has been cordoned off with high-level security at the site,” she said.
“France has been on a state of emergency after string of attacks for the past few years. And there are high-level of alert group of soldiers in several public places in Paris.”
A spokewoman for the Louvre said the museum was “closed for the moment” but would not confirm reports it had been evacuated. A Reuters witness at the scene said police had cordoned it off.
The huge former royal palace in the heart of the city is home to the Mona Lisa and other world-famous works of art but is also a shopping complex and houses numerous exhibition spaces.
France has suffered a string of attacks, beginning in January 2015 when gunmen killed cartoonists and journalists at the offices of the Charlie Hebdo, a satirical newspaper in Paris in revenge for publishing cartoons of the Prophet Mohammed.
Another attacker went on to kill shoppers in a Jewish supermarket, bringing the total number of people killed to 17 in three days of bloodshed.
Ten months later, gunmen and suicide bombers from the Islamic State of Iraq and the Levant (ISIL) group attacked bars, restaurants, a concert hall and the national stadium in Paris on November 13, 2015, killing 130 people.
Last July, a Tunisian man rammed a lorry through crowds celebrating Bastille Day in Nice on France’s south coast, crushing 86 people to death.