A Baltimore judge has overturned the conviction of Adnan Syed for the murder of his girlfriend.

Syed, who was the subject of the massively popular podcast series 'Serial' in 2014, was imprisoned in 2000 at the age of 19. His girlfriend, Hae Min Lee, was found dead in Leakin Park, Baltimore in 1999.

Prosecutors last week asked the court to throw out his conviction, saying a year-long case review had turned up two "alternative suspects".

Now 41, Syed was released into home detention. Baltimore Circuit Judge Melissa Phinn said she was vacating his conviction "in the interest of fairness and justice", adding the state had failed to share evidence that could have helped his defence at trial.

However, Syed's release does not mean he is innocent and a new trial date will be set in the future.

'Serial', a 12-part true-crime series following the case was created by journalist Sarah Koenig.

The podcast won a Peabody Award and is often regarded for bringing the format into popular culture.

Koenig's podcast raised various doubts over Syed as the murder suspect. It featured multiple recorded calls between Syed and Koenig from prison where he maintained his innocence throughout his stay.

'Serial' continued on with two more seasons following different cases in 2016 and 2018. Koenig will return to the season one case with a new episode tomorrow.

You can listen to the new episode of 'Serial' on Spotify when it drops here.