More than 11 hours of combined police body cam footage from 30 videos has been released to ABC’s “World News Tonight with David Muir” as well as “Nightline.” The grueling footage shows police helping survivors of the mass shooting at the Pulse nightclub, a popular venue for gay people in Orlando, while pursuing Omar Mateen, the shooter. 49 people were killed that night and 53 others were injured, as Mateen carried out an act of revenge for U.S. actions in Syria.

The incident happened slightly over 24 hours after Christina Grimmie, a young singer, was shot and killed outside the nearby Plaza Theater in Orlando while signing autographs.

Omar Mateen entered Pulse nightclub in Orlando, Florida

In happened on June 12, 2016, when Mateen entered the Pulse nightclub in Orlando, Florida carrying an assault rifle. He opened fire shortly after 2 a.m. The video reveals the 911 calls from people at the club calling for help. It also plays the 911 calls made by Mateen himself.

While the bodies have been blacked out in the video it is still a horrific scene as police arrive at the club. The first officers to arrive at the nightclub shoot at Mateen, which forced him to move deeper inside the club.

The officers make their way through, having to ignore the bodies of those injured and killed, as their protocol is to go after the active shooter.

It took the officers three hours to get control of the situation at the Pulse nightclub, which some have criticized, but Orlando Police Chief John Mina said the officers made the right call.

They had to get the shooter before he killed any more victims.

Tracking down Omar Mateen took three hours

According to Mina, over the course of those three hours, officers were saving people from the dressing rooms, the dance floor and from one of the bathrooms. They took a total of 22 people out of the front bathroom of the club.

He adds that once they were inside the Pulse nightclub the shooting stopped, until the final assault against Mateen.

At one point officer Brandon Cornwell is filmed as he enters the club via a broken window. He takes took cover close to one of the bars, while Mateen was holed up in a bathroom nearby where he had taken hostages. Shots are heard and one of the officers yells at Mateen, telling him to show his hands, or he will die. The sound of Cornwell’s voice is heard on the video, asking Jesus to watch over him.

While Mateen called police emergency dispatch on several occasions from inside Pulse nightclub, he repeatedly pledged his allegiance to Abu Bakr al-Baghdadi, the leader of the Islamic State.

He urged the police to stop the U.S. airstrikes in Syria. A police negotiator used this moment to keep Mateen talking, allowing officers to take as many survivors as possible out of the club before the final showdown.

SWAT team arrives at Pulse nightclub

The incident had gone from what was an active shooter situation to a hostage situation and SWAT teams can be seen in the videos, setting up outside. Once the SWAT team was inside, Mateen finally surfaced and started shooting at them. As reported by Orlando Weekly, in the hail of bullets that ensued, Mateen was finally taken down shortly after 5 a.m.

Omar Mateen, 29, was the American-born son of Afghan immigrants who was working as a security guard in Port St. Lucie. He is described by ABC News as a troubled and angry man with a history of violence.