Migrants are continuing to overwhelm Border Patrol agents at the busiest border crossing in the US, and holding centers are still over capacity — despite the Biden administration’s assertions that a “crackdown” on crossers is working.

Border Patrol facilities in the San Diego region were at 150% capacity with more than 1,500 migrants in custody as of Tuesday morning, according to internal agency data leaked to The Post.

The holding centers in the region were meant to detain just 1,000 people.

Migrants are choosing to cross into San Diego because there are many exemptions to Biden’s rule there, border agents tell The Post. VCG via Getty Images

The facilities were already above capacity before President Biden’s June 4 executive order took effect. The order was designed to limit the ability of many migrants to claim asylum while border crossings remain high.

However, there are major loopholes and exemptions in the order that allow migrants to continue to stay in the US. And one of the biggest loopholes is in San Diego.

Even as crossings have fallen to the lowest levels of the Biden Administration elsewhere, the San Diego-area migrant holding facilities are still over-flowing, said Manny Bayon, National Border Patrol Council President for the San Diego sector.

Bayon said that’s because migrants who cross into the San Diego region have a better chance of skirting the rules and staying in the country due to an order, previously reported by The Post, that agents should release migrants from more than 100 countries in Europe, Asia and Africa.

Migrants from those countries are harder to deport because their home governments don’t readily accept deportation flights.

Many of the migrants coming through the San Diego sector are from “all over the world,” a border patrol agent in the region told The Post.

“China, India — there’s a lot of Indians, there’s just like a s–t ton — and Central Americans,” the agent said.

Migrants from more than 100 countries are being released into the US in the San Diego sector, exempt from Biden’s executive order. REUTERS

“A lot of these guys are not, they’re not Mexicans. They’re from all over the world,” a border agent in the San Diego region told The Post. Anadolu via Getty Images

The agent said that, in practice, anyone who is pregnant or injured is also being released with a future court date, despite Biden’s crackdown order.

Across the southern border, migrants who arrive as unacompanied children, or those who come at a legal port of entry using the CBP One phone app are also exempt from the policy’s restrictions.

Migrants who aren’t exempt from the executive order also have the opportunity to stay if they claim to have a fear of returning to their home country.

Roughly 30,000 illegal border crossers were released into the country with upcoming court dates, according to leaked documents obtained by The Post.

Last month, Department of Homeland Security Secretary Alejandro Mayorkas claimed that the executive order was working “because of their tough response to illegal crossings.”