Muslim ghettos in Paris and Brussels are incubators of Islamic extremism where police fear to tread, crime and unemployment are rampant and radical imams aggressively recruit young men to wage jihad against the West, experts said Tuesday.

The identities of the terrorists who attacked an airport and subway station in Belgium remained unclear.

But the perpetrators of last November’s bloody attack on Paris and other terror strikes in Belgium and France hailed from Molenbeek, a Brussels slum that has long been a hotbed for radical Islam, drugs and lawlessness.

Others, including the brothers who carried out the Charlie Hebdo massacre in January 2015, lived in the “banlieues,” or suburbs of Paris, desolate, run-down neighborhoods of shops, mosques, and high-rise apartment buildings built 50 years ago to house waves of immigrants from former French colonies in Africa.

“Both in Paris and Brussels we have seen the radicalization of individuals which has led to these cowardly attacks on civilians. Unfortunately, these poor neighborhoods in which they live act as breeding grounds for terrorism because many of these people feel as if they have no other options or hope,” a senior anti-terrorism official told The Post.

Salah Abdeslam, 26, the architect of the November Paris attacks, which left 130 dead, was found last week hiding in an apartment in Molenbeek.

And other residents of the neighborhood have been linked to nearly all of Belgium’s terrorism-related incidents in recent years.

Moroccan national Ayoub el-Khazzani, who opened fire with a Kalashnikov on a high-speed train in August, lived in Molenbeek.

Mehdi Nemmouche, a French-Algerian who killed four people at the Jewish Museum in Brussels last year, spent time in the ghetto.

And two suspected terrorists gunned down by Belgian cops in a shootout in the town of Verviers in January were from Molenbeek.

‘These ghettos are called ‘no-go zones,’ very deprived areas in many northern European cities. I call them stateless, they’re not accepted in France and Belgium.’ - Soeren Kern, a senior fellow at the Gatestone Institute

Roughly 500,000 Muslims are believed to live in Belgium, about 6 percent of the population.

The Brussels ghetto has a 30 percent unemployment rate, and hundreds of young radicalized Muslim men have travelled to Syria to wage jihad, Belgian officials admitted.

“I notice that each time there is a link with Molenbeek. This is a gigantic problem. Apart from prevention, we should also focus more on repression,” Prime Minister Charles Michel said after the Paris attacks.

“These ghettos are called ‘no-go zones,’ very deprived areas in many northern European cities. I call them stateless, they’re not accepted in France and Belgium. I think it’s the despair, and their radical preachers take advantage of that. They draw them into the mosques, and that’s how the radicalization happens,” Soeren Kern, a senior fellow at the Gatestone Institute, a New York-based think tank focusing on international studies.

So-called “no go” zones, he added, are not formal designations by law enforcement, but an informal understanding that they are areas that are crime-ridden, run by drug dealers and gangs not safe for non-Muslims — even police and firefighters.

“There was a case in France where a mosque was on fire, and when the firefighters arrived to put it out, the local youths stoned them. It’s very dangerous,” he said.

Roughly 5 million Muslims, Europe’s biggest Islamic population, live in France, most of them in the housing projects surrounding Paris, where unemployment rates are around 25 percent.

The Charlie Hebdo attackers, Saïd and Chérif Kouachi, lived Gennevilliers, a suburban neighborhood that’s home to 10,000 Muslims.

Amedy Coulibaly, the terrorist who murdered a policewoman on Wednesday and seized control of a kosher grocery on Friday before police killed him, also most recently lived in a Paris banlieue.

And the nightmare is not going away any time soon, a second counter-terrorism source said.

“This a problem that’s going to be with us a for a very long time. I think we’re talking generations — our children and grandchildren are going to be facing this problem,” said the source, a retired intelligence officer said.

“They speak their own language, they live in their own microcosm. They are isolated. They have no upward mobility. In those European societies, they are very class conscious and stratified,” he said.

“You read ISIS propaganda on the Internet and social media. Your mind becomes fertile ground for radicalization.”