A Maryland man has been freed from prison after spending 13 years behind bars for a murder he didn’t commit.

Lamar Johnson, 34, was convicted of first-degree murder in the death of Carlos Sawyer, 31, who was fatally shot in broad daylight in East Baltimore in 2004.

An informant identified the shooter by a nickname that investigators thought belonged to Johnson.

Two teenage witnesses to the crime later identified Johnson as the killer, “but their testimony was riddled with problems,” according to the Mid-Atlantic Innocence Project [MAIP], which helped exonerate Johnson.

A credible witness identified the actual killer at Johnson’s trial as another man, who fought with and threatened Sawyer with a knife 15 minutes before he was gunned down, authorities said.

In addition, Sawyer’s own family believed Johnson did not kill their loved one.

“We don’t want to let Carlos’ murder create two tragedies,” a relative told MAIP.

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Still, Johnson was found guilty and sentenced to life in prison.

No physical evidence connected him to the murder and authorities were never able to establish a motive, according to MAIP.

While imprisoned, Johnson saw a poster for MAIP. He wrote to them saying he was innocent.

The organization took on Johnson’s case in 2010, assembling a legal team that included attorney David Benowitz of D.C. law firm Price Benowitz to free him.

“Although an obvious case of innocence, there were roadblocks making it difficult to pursue in court,” MAIP said.

Johnson’s legal team identified several witnesses who exonerated Johnson and corroborated the trial testimony about the alleged identity of the real killer.

Read: Man Wrongfully Convicted of Murder Released From Prison After 32 Years

In 2016, MAIP brought the case to the Conviction Integrity Unit, which executed its own investigation. They joined MAIP’s request to the trial court to vacate Johnson’s conviction.

“Lamar’s case underscores the benefits of true collaboration between innocence organizations and real, robust conviction review units that look beyond procedural problems and dig for the truth,” said Shawn Armbrust, MAIP Executive Director. “This case should serve as a model for other units around the country.”

Johnson walked free on Tuesday.

“I’m just so blessed right now,” an emotional Johnson told reporters one day after being released. “It’s a wonderful feeling.”

Johnson, who got his GED while incarcerated, said he hopes to make the most of the rest of his life. He plans to pursue further education, eyeing entrepreneurship and help others who have been wrongly convicted.

"All I can do is just, now that I have got a second chance at life and have freedom again, [is] be a better productive citizen in society,” he said.

Watch: Man Wrongfully Imprisoned 31 Years Gets Just $75 For His Trouble