A Pakistani court has acquitted 20 people of charges that they were part of a lynch mob who burned alive a Christian couple that had been falsely accused of blasphemy in 2014.

Brick-factory workers Shahzad Masih, 26, and Shama Shahzad, 24, were burned alive in an industrial kiln by a mob that had been incited by accusations the couple desecrated the Koran near the town of Kot Radha Kishan in Punjab by throwing away pages of the Islamic holy book along with the trash.

After the attack, it emerged that the couple had been falsely accused.

Police arrested scores of villagers in the case.

An antiterrorism court in Lahore in November 2016 sentenced five men to death and 10 others were given varying jail terms for playing a supportive role in the killings.

That court also acquitted 93 suspects in the case in 2016.

Prosecutor Abdur Rauf says the court on March 24 acquitted 20 other suspects who had been indicted in the case at a later stage.

The killings triggered international criticism of Pakistan's blasphemy laws, which were introduced in the 1980s.

Blasphemy is a sensitive issue in Pakistan and a mere allegation can often prompt mob violence.

The U.S. State Department has said Pakistan’s blasphemy laws are often used as justification for mob justice.

With reporting by AP