The Calais migrant camp, dubbed The Jungle, has long been a gathering point for refugees hoping to cross the English Channel for a new life in the UK.
The population has recently expanded while France has fought to maintain security and to provide temporary housing for the migrants, many of whom sleep in ramshackle tents.
But the situation has been getting out of control and security has become almost impossible to enforce, a police officer at the scene told Le Figaro newspaper on Friday.
"It's truly mind boggling what's going on there," said the officer of the CRS force, which is tasked with maintaining public order. "It's worse than ever."
"It's impossible to know if, for example, a jihadist from Belgium is hiding in there. This camp is a blind spot for national security in the middle of the state of emergency."
Authorities have estimated that around 4,500 people are living in the camp, which sprawls across the outskirts of the city of Calais in northern France.
But the police source said that judging by the sheer number of meals handed out each day, the camp's population must be closer to 7,000.
However aid agencies suggest the population is even higher.
A census from the Auberge des migrants group that was released on Thursday puts the population at 8,922.
The bulging population comes with a myriad of concerns that have extended beyond housing and health.
On Friday, a French court ruled that the scores of illegal shops eateries in the camp should not be closed down, noting that they were important gathering spaces for people facing "extreme hardships".
Authorities had sought to close 72 unlicensed stalls and restaurants dotted among the tents on sanitary reasons.
Other concerns include a rise in prostitution and a serious few incidents of violence.
Late June saw a violent clash that resulted in the fatal stabbing of an Ethiopian. A month earlier a massive brawl between Sudanese and Afghani migrants left 20 injured, including volunteers.
Denis Hurth of the Unsa-police union told Le Figaro on Friday that France's terror threat has seen officers deployed to all the big cities of France, and that Calais as a result has been left by the wayside.
He said that only eight CRS units operate in Calais and just three squadrons of paramilitary police, which he said was hardly enough to "deal with mammoth problems of public disorder".
And despite efforts from French authorities, the situation doesn't appear to be improving.
Authorities have already cleared the southern part of the camp and added metal shipping containers kitted out with heaters, electrical sockets and cots for babies, but many migrants refused to move into the containers.
Instead, they piled into the northern stretches of the camp together with other new arrivals, creating a pressure-cooker like area that apparently seems ready to burst.
France's housing minister latest plan to ease the strain saw her announce this week that the government would create an additional 3,000 bed spaces in reception centres "before the end of September", more than doubling the current figure of 2,000.
She also called on the French public to open their doors and invite a refugee in.
But with many thousands of migrants in the Jungle only having eyes for the UK, it's unlikely that the extra beds will do much to help.