A Chicago police officer was shot to death while driving home from work early Sunday on the Southwest Side, according to city officials.

Officers responded to a ShotSpotter alert about 2:55 a.m. and found Officer Luis Huesca suffering from multiple gunshot wounds in the 3100 block of West 56th Street, a police spokesperson said in a statement.

Huesca, who was still wearing his uniform, was taken to the University of Chicago Medical Center and pronounced dead. Police Supt. Larry Snelling told reporters outside the hospital hours after the shooting. Snelling said Huesca had been on the police force for six years and was just two days shy of his 31st birthday.

The shooter or shooters remained at large, Snelling and Mayor Brandon Johnson said.

“We lost one of our own today,” Snelling said. “He was just a great officer, great human being.”

Roughly 30 gunshots were fired during the attack, although it’s unclear whether Huesca fired in self defense, according to law enforcement sources. His Toyota 4Runner was taken after the shooting and was later recovered nearby.

Sources said the shooting happened during an apparent carjacking, but Snelling only said Huesca’s vehicle had been stolen.

Huesca’s gun and badge weren’t found at the scene, sources said.

In a letter to department members, Snelling said Huesca had been on the police force since 2018 and was detailed to the office of Area 2 Deputy Chief Senora Ben.

“There will be sadness, anger and grief as we ask how the life of our fellow brother could be taken in this reprehensible act of violence,” Snelling told fellow police officials. “Our focus right now is on his family and loved ones who are going through the unimaginable trauma of loss. We are also focused on apprehending whoever is responsible for this.”

In a statement, Mayor Johnson described the shooting as “an act of unconscionable gun violence in our city.”

“I met with Officer Huesca’s mother and uncle this morning and assured them that they have the full support of my administration as they deal with this unspeakable loss,” Johnson said. “Our city is grieving, and our condolences go out to their entire family as well as Luis’ fellow officers and community.”

Johnson said Huesca had been working in a specialized unit in the Calumet District known as the Priority Response Team.

The mayor vowed to commit “every resource available toward apprehending anyone involved in this morning’s shooting and bringing them to justice.”