Egypt's highest appeals court has overturned death sentences for 36 members of the Muslim Brotherhood, which the government has labelled a terrorist group, and ordered a retrial.

It's the second time in two months that the Court of Cassation reversed death sentences handed down to Islamists in cursory mass trials, which rights groups and Western governments have widely condemned.

The state MENA news agency said Wednesday's case stems from an August 2013 attack on a police station in the southern town of el-Adwa when a police officer and a civilian were killed. Such revenge attacks swept across Egypt following a security crackdown on ousted President Mohammed Morsi's supporters that killed hundreds.

Over 140 Islamists were also sentenced to death in absentia in the same case, including a top Brotherhood leader.