NBC 5 Investigates has new information on what happened inside El Centro College the night of the attack as police continue to make progress collecting evidence at the scene.
El Centro police Cpl. Bryan Shaw and Officer John Abbott were among the officers injured in the deadly ambush Thursday night.
Cell phone video shot inside the college shows police searching for Micah Xavier Johnson who had already wounded officers outside before shooting his way into the building.
The latest news from around North Texas.
"The doors exploded from gunfire. Two of my officers sustained injuries. One of them had glass fragments that entered his legs," said El Centro Police Chief Joseph Hannigan.
Hannigan says his officers continued to fight, helping Dallas SWAT officers who pursued Johnson to the second floor of the building during the gun battle, despite their injuries.
“[Johnson] was letting rounds go. SWAT was returning rounds. It was an extreme gun fight,” said Hannigan.
With the suspect cornered in an alcove on the second floor, SWAT negotiators took over ultimately using a bomb delivered by a robot to end the standoff.
Fifty-eight students trapped inside the building all survived the attack.
Tuesday, the campus is still considered a crime scene, five days after the shootout.
The FBI still has collection teams helping Dallas police.
Hannigan believes the incident could have been worse if not for his cops who rushed toward the danger.
“I’m extremely proud of them and the Dallas Police Department who showed extreme bravery that night,” said Hannigan.
Sources tell NBC 5 Investigates Johnson had three weapons, two semi-automatic pistols, in addition to a rifle. Investigators have not said where Johnson bought them but the ATF is investigating.
Police say they’ve made a lot of progress reducing the size of the area that still needs to be processed.