Shaurn Thomas after he was released form prison in Frackville, Pennsylvania, on Tuesday (23 May). Twitter / PA Innocence Project‏ / @innocencepa

A man who spent 24 years in prison for a murder he did not commit has been exonerated and freed with the aid of a former policeman.

Shaurn Thomas was jailed in 1993 for the murder of Puerto Rican businessman Domingo Martinez, who was shot dead taking a $25,000 (£19,273) to a check-cashing store three years earlier.

The 43-year-old was released after the Philadelphia District Attorney's office agreed that the evidence did not support the conviction.

The case has been worked on by lawyers from the Philadelphia Innocence Project around 10 years ago with former Philadelphia police sergeant James Figorski working pro bono for more than eight years on behalf of Thomas, who was just 19 when he was jailed.

Thomas was released from prison in Frackville, Pennsylvania, where he celebrated with his fiancée Stephonia Long and his long-suffering mother on Tuesday evening (23 May).

"I feel wonderful, a free man. I can't feel no better," Thomas told 6abc. "Hey man, just got to believe in God, and had the right legal team, and keep fighting."

Despite losing more than two decades of his life Thomas said he held no grudges towards those that jailed him.

"What for? Life's too short for that. You can't get it back. I just move on forward. It's a tragedy that happened to me, but I'm pretty sure I'm not the only one," he said.

Thomas maintained all along that he was innocent, saying that he was actually at a correctional centre for youth offenders for an unconnected case at the time of the slaying.

The log book for the correctional centre had gone missing and jurors did not believe his family when they said they were with him.

The BBC reported that his case file, which named several other suspects, had been lost for decades but was discovered recently.

"Shaurn engaged in a decades' long struggle to prove his innocence," Figorski said in a statement.

"I joined him in that struggle, and many times it seemed that we would never succeed and he would remain in prison for the rest of his life."