HOUSTON – A Houston police officer was fighting for his life after he was hit by a vehicle and dragged Wednesday on Southwest Freeway at Greenbriar while serving a warrant, police said.

Investigators said Officer Nestor Garcia, 24, spotted a stolen vehicle and followed the driver while he waited for backup. When officers arrived, they pulled the suspected car thief over in the emergency lane of Highway 59 and blocked off one additional lane, investigators said. When they got out of their units, another driver, 79-year-old Robert Zimmerman, hit Garcia and dragged him along the road, police said.

Zimmerman was driving 50 to 60 mph when he hit the victim, Houston police Chief Art Acevedo said.

“This was person that acted with an abandoned heart,” Acevedo said.

Garcia was taken to Memorial Hermann Hospital and into surgery. He was listed in critical condition, police said. Several hours later, Acevedo said Garcia was out of surgery but "not out of the woods."

One of Garcia's doctors outlined his injuries saying he suffered a head injury, abdominal injuries and fractures.

Acevedo said Garcia was awake, responsive, and giving the thumbs up sign. Garcia remains in the ICU in critical, but stable condition.

The Houston Police Department is asking the community to donate blood in Garcia's name for both Garcia and others in need. Contact the Gulf Coast Regional Blood Center if you're interested.

Houston Mayor Sylvester Turner, Acevedo, doctors and other officials asked the public to pray for Garcia.

We are at Memorial Hermann with Officer Nestor Garcia's family & extended @houstonpolice family, we need prayers. pic.twitter.com/pWNsZl75L8 — Chief Art Acevedo (@ArtAcevedo) September 27, 2017

He is a rookie that has only been on the force for a little more than a year.

Acevedo said Garcia is "a really well-liked kid" whose family is from Mexico. Fellow officers nicknamed him "Nacho."

Police are investigating whether Zimmerman was under the influence of drugs or alcohol.

Acevedo expressed his zero tolerance for driving under the influence.

“You know how I feel about drunk(en) driving. There’s no excuse for it. There’s no excuse for driving under the influence of alcohol or drugs,” Acevedo said. “Quite frankly, if it turns out through the investigation that the person is under the influence, we need to hold people accountable.”

Turner, who spoke with the family, said that the whole city of Houston is standing with them.

“We want the family to know they are not going through this by themselves,” Turner said. “The city of Houston, we are their family. They have a very extended family.”

UPDATE: "He's really sick right now," @ArtAcevedo talks about Officer Nestor Garcia. He remains in surgery. @KPRC2 pic.twitter.com/L88ckGRsiL — KPRC Cathy Hernandez (@KPRC2Cathy) September 27, 2017

Zimmerman was arrested and charged with intoxication assault of a public servant.

Family members described Zimmerman as a sweet and generous man, who is beloved in the community.

Prosecutors said Zimmerman has no criminal history in Harris County.

He is expected in court Thursday.

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