French President Emmanuel Macron Tuesday launched a weeks-long operation against drug trafficking in Marseille, saying gangland battles that last year left dozens dead had made life impossible for many residents.

Making an unannounced visit to the southern port which later this summer will host some Paris 2024 Olympics events, Macron said more than 80 people had already been detained in the first raids.

"In Marseille and other cities in France, we have launched an unprecedented operation to put a stop to drug trafficking and ensure republican order," Macron wrote on X, formerly Twitter, after arriving in the city.

Some 4,000 police officers will be mobilised every week in Marseille and the surrounding areas for the next three weeks, according to a source close to the issue.

Macron began his visit with a walkabout in the northern district of La Castellane, telling residents in one of the worst hit areas that the operation will "try to destroy the networks and the traffickers."

 'Growing scourge' 

Macron said 82 people have already been detained with 60 of them remanded in custody for further questioning.

"Drug trafficking is a growing scourge" and "the situation is very difficult" in Marseille and other cities, he said, adding France was in the throes of a "battle" against the dealers.

"Based on the in-depth work that has been carried out for years, we identified... the people who we know make life impossible for a neighbourhood," he said.

As Macron talked to locals from the area, which has a large Muslim population, he found however that the war in Gaza came up as much as drug issues, with residents urging France to do more for the Palestinians.

"We have given all the means necessary to Ukraine to defend its rights. Today, what are we doing for Palestine, Mr Macron?" Ahmed Said, 35, told the president.

Questioned by one woman who tearfully told the president she could not sleep because of the fate of the Palestinian children in Gaza, Macron replied: "I share your distress and I have heard it," adding: "The nature of the operations carried out (by the Israeli army) is unacceptable."

The bloodiest ever Gaza war broke out after an unprecedented attack by Palestinian militant group Hamas on October 7 that resulted in about 1,160 deaths in Israel, mostly civilians, according to an AFP tally of Israeli official figures.

Militants also seized about 250 hostages, of whom Israel believes 130 remain in Gaza, including 33 who are presumed dead.

Israel has responded with a relentless offensive against Hamas that Gaza's health ministry says has killed at least 31,819 people, most of them women and children.

Macron later warned that the conflict "should not give rise to any hatred within the (French) republic".

 'Asymmetrical war' 

The turf war for control of lucrative deal-making points in Marseille hit new highs in 2023, with 49 people killed and 123 people injured.

Four of those killed had no link to drug wars and were caught by accident in crossfire.

"You can calm down your little CRS (anti-riot police)," one youth told the president.

"Sending them here won't make any difference."

The situation has been calmer so far this year but could erupt again at any moment, said Marseille prosecutor Nicolas Bessone.

The campaign by the French authorities comes after the alleged leader of a major drug gang from Marseille was arrested in Morocco last week.

Felix Bingui, 33, was detained in the port city of Casablanca.

Bingui is believed to be the leader of Yoda, one of Marseille's main drug gangs, which has been engaged in a turf war with another major clan known as DZ Mafia.

Tackling the issue is all the more important for the French authorities as Marseille has a role to play in this summer's Olympics in the capital Paris.

Marseille is due to provide a spectacular backdrop as it hosts the Olympic sailing events and its legendary Velodrome stadium will also host some matches in the Olympic football tournament.

"Narcotics crimes in Marseille are a kind of gangrene which damages the social fabric," Marseille's top judge Olivier Leurent said earlier this month, adding France seemed to be waging an "asymmetrical war against drug crime".