What a group of undercover officers hoped would be a quick and routine arrest of two suspected heroin dealers Tuesday afternoon in Gretna quickly turned into a frantic effort by the men to escape. It ended with them, and one officer, leaving the scene in ambulances after being shot.

The officer was not seriously wounded because he wore a bulletproof vest, Gretna Deputy Police Chief Anthony Christiana said.

One suspect, identified as Darryl Johnson, 22, was in critical condition after being shot in the face. The other suspect, Darrin Jones, 23, was shot multiple times and was in stable condition, Christiana said.

The shooting happened about 3 p.m. behind a strip mall at Claire Avenue and the West Bank Expressway.

Christiana said Johnson and Jones arrived there in an effort to sell heroin to officers who are part of an undercover task force made up of Gretna and Westwego police and Jefferson, Plaquemines and Orleans Parish deputies.

Once the car driven by Johnson arrived, the officers blocked it in from the front and back, Christiana said.

Johnson threw the car into reverse and began to slam into the police cars in an effort to escape, Christiana said.

Several of the officers got out of their cars, at which point Johnson accelerated toward one, Christiana said. That officer was able to hop out of the way and was not hit.

Johnson again reversed his car before driving forward toward officers, Christiana said.

At that point, one officer opened fire on the car and was struck by the car, being pinned between the car and a fence, Christiana said.

The officer opened fire and felt what he thought was a bullet strike his vest, Christiana said.

The vehicle again went into reverse.

“With all this happening simultaneously,” Christiana said, “officers opened fire fearing for their lives and the life of the officer who was down.”

The other officers were able to break into the vehicle and put it in park.

A semi-automatic handgun was found in the front seat area of the car but it was not immediately clear if it was fired or if the officer was struck by his colleagues when they began to shoot.

The officer was taken to a hospital, where he was in good condition with shrapnel abrasions and cuts to his arm.

Even with a vest on, Christiana said, being shot has the same effect.

“An officer sustains the same impact when that round hits that vest. The only thing that doesn’t happen is that bullet doesn’t penetrate,” he said. “The only thing is the projectile does not enter the body.”

Johnson has an “extensive” criminal history, Christiana said, and is on probation for various drug charges. He has several prior arrests for drug and gun violations.

Jones also has a lengthy record and is on parole until 2019 for second-degree murder and is serving probation for illegal carrying of weapons.

Christiana said Jones has outstanding warrants for illegal carrying of weapons and possession of controlled dangerous substances.

Gretna police said the suspects will face new charges related to Tuesday’s shooting.

Follow Danny Monteverde on Twitter @DCMonteverde.