Investigators looking at the shooting scene last week. (Brandon Wade/AP)

The gunmen who attacked a cartoon contest depicting the prophet Muhammad in Texas earlier this month were killed by multiple officers on a SWAT team, rather than a sole traffic patrol officer, as police had initially said after the encounter.

This new information was released by Garland’s police chief on Monday during a news conference seeking to emphasize that his department had no warning that the gunmen would target the contest and cartoon exhibit.

In the initial narrative outlined the morning after the incident occurred, Garland police said the two gunmen drove up to the center and opened fire in the parking lot, hitting a school security officer in the leg. A police spokesman said last week that an officer who normally works on traffic, but who was at the event as part of a heavy security detail, shot and killed both gunmen using his duty pistol.

On Monday, Mitch Bates, the Garland police chief, clarified details of this shootout between the gunmen and five of his force’s officers.

Bates said that the officer and the security guard who were confronted by the armed gunmen were not in a police car, as was initially believed, but were standing by it when the gunmen drove up to a barricade and got out of their car.

In addition, Bates said that the Garland police officer, who has not been identified, shot the gunmen and wounded, rather than killed, both of them. Four SWAT members armed with assault rifles and pistols came over within seconds, Bates said, and after dozens of rounds were fired from police and the suspected shooters, both gunmen had been killed.

Elton Simpson, 30, and his roommate, Nadir Soofi, 34, traveled from Phoenix to the inflammatory contest, which offered $10,000 for the best cartoon depicting Muhammad. Drawings of Muhammad are considered blasphemous by many Muslims, and the show had drawn worldwide attention from jihadists calling for attacks in Garland.

The mother of one of the gunmen in Sunday's Mohammad cartoon attack says her son was not a violent person. Sharon Soofi said she doesn't blame police for shooting Nadir but is left feeling "empty." (Reuters)

Bates said on Monday that the two men had six guns between them — three assault rifles and three pistols — as well as hundreds of rounds of ammunition on their bodies and in their vehicle. He said there were no indications that anyone else was involved in the attack, but said the investigation is ongoing.

The FBI had known about Simpson for nearly a decade, since it began investigating him and he was eventually suspected of trying to fly overseas to wage jihad.

FBI Director James B. Comey told reporters at a briefing last week that his agents sent an intelligence bulletin to authorities in Garland about three hours before the attack with information about Simpson. Comey said the FBI learned around that time that Simpson was possibly interested in going to Garland, so he said they sent local authorities a photo of him and information that they had.

But he said that the FBI had no reason to believe that Simpson had left Phoenix or was going to attack the event, only that he may have been interested in going to the event.

“We didn’t know more than that,” he said.

During his news conference Monday, Bates said that no one in his department or at the command post for the event’s security knew about this e-mail before the shooting.

But he also emphasized that the e-mail would not have changed what happened that day, saying that the bulletin couldn’t have prevented the shooting or changed the way law enforcement officials responded. He praised the officers who engaged in the shootout with Simpson and Soofi as heroes “who put their own lives at great risk.”

Bates also said Monday that the police were not releasing the names of any of the officers involved in the episode due to what he called “direct and indirect threats to their safety and the safety of their families.”