Update 10:35 PM, 5/11/17: Sources tell NY1 the city's embattled correction commissioner, Joseph Ponte, is leaving his post.

Mayor Bill de Blasio has been defending his embattled correction commissioner, Joseph Ponte, for weeks. All along, he has claimed Ponte has made the city jails safer. NY1 took a closer look at the numbers and found that may not be the case. Our Courtney Gross has the story.

Mayor de Blasio thinks Joe Ponte has made Rikers Island a better place:

De Blasio: Commissioner Ponte has done an extraordinary job for this city.

De Blasio: He has fundamentally changed the nature not just of Rikers but of the correction system in three years.

De Blasio: I look at his results. I look at the integrity. I have seen in him and the way he has handled the job.

De Blasio: He has made it safer. He has made it more humane.

NY1 dug up the numbers. Some of them tell a different story.

For one, stabbings and slashings on the island have skyrocketed, increasing 32 percent when you compare the first nine months of this fiscal year to the same time period the year before.

The same can be said about inmate fights, which increased 19 percent.

Meaning, Rikers may not be safer at all. By some accounts, it's more violent.

Critics tell NY1 that it feels as though the inmates are in charge instead of the officers.

For example, last fall a photo provided to NY1, seen in the video above, shows a group of officers trying to keep the doors shut as inmates on the other side attempt to rush through.

Another example seen in the video above shows how inmates hide blades or scalpels in their rectums — the same contraband responsible for the massive uptick in slashings.

When asked Thursday, de Blasio acknowledged that Rikers is not exactly safe.

"Look, there are some things on Rikers that are factually true that we are not happy with," the mayor said. "There are some categories of violence and other problems that have gone in the wrong direction.

"I am very comfortable saying that we're not happy with it," de Blasio said. "We are not going to accept it, and we have a lot of efforts in place to turn that around."

The mayor's staff is also quick to point to other statistics.

Use of force among officers is down, and serious injuries among staff decreased 21 percent.

That is what City Hall would like you to focus on:

"You're talking about a guy who inherited a mess," de Blasio said. "And I would say we aren't anywhere near done; there is more to do on violence, for sure."