BALTIMORE (WJZ) — Two men are under arrest in the shooting of Baltimore Police Officer Keona Holley, and they’re suspected of carrying out a murder hours later, Police Commissioner Michael Harrison said Friday.

Elliot Knox, 31, and Travon Shaw, 32, are charged with attempted murder in Officer Holley’s shooting and murder in the shooting death of Justin Johnson, who was killed early Thursday in Yale Heights, Harrison said.

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“These incidents are tragic reminders of the culture of violence that pervades Baltimore. Life is precious and sacred, but unfortunately, there are those who have no regard for it,” the commissioner said. “BPD is committed to the preservation of the lives of everyone in our city. We will always work to bring justice to all victims of violence.”

Harrison said police recovered two guns from a Baltimore County home that are linked to the shootings, one of which has been confirmed by ballistic tests to have been used in both cases.

Keona Holley

He said both men, who have extensive criminal records spanning multiple jurisdictions, admitted to their roles in the shootings, but a motive remains unclear at this point.

“We don’t know why they did this,” the commissioner said. “We have absolute confessions that they did it, they were there. We don’t have motive as to why.”

After recovering a vehicle of interest Thursday, detectives tracked down a person of interest, who was brought in for questioning, Harrison said, and police later took a second person of interest into custody.

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Officer Holley remains on life support in the intensive care unit at Shock Trauma, said Harrison, who described the officer’s condition as critical but stable.

Holley was seated in her patrol car In Curtis Bay about 1:30 a.m. Thursday when someone opened fire into the vehicle, police said. Shot multiple times, Holley was rushed to the hospital with life-threatening injuries.

Roughly two hours later, police said, Johnson was shot in the 600 block of Lucia Avenue in the Yale Heights neighborhood. He was pronounced dead at the scene.

“What we now know is that both shootings are related,” Harrison said.

Based on preliminary information, police believe that the men knew Johnson, Harrison said, but they don’t know if he knew them. It’s unclear whether Holley knew them.

“We don’t believe it’s random, but we also at this time, still early in the investigation, don’t have the answer as to whether or not there are previous contacts,” he said. “That’s what’s being investigated.”

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Knox and Shaw are in custody at Central Booking where they’re awaiting court proceedings in both cases.