Senegal's parliament has approved revisions to an amnesty law covering 2021-24 protests, paving the way for possible prosecutions over the deaths of dozens of protesters.

The law was passed in March 2024 under former President Macky Sall, and offered amnesty for offences committed by both security forces and protesters during demonstrations that saw clashes involving armed riot police.

The protests were triggered by concerns that Sall was trying to muzzle his opponents and cling to power past the end of his mandate, which he denied.

Amnesty International has said at least 65 people were killed, mostly by bullets.

The standoff, exacerbated by the arrest of Sall's political rival Ousmane Sonko in 2023, became one of the most violent episodes in Senegal since it gained independence from France in 1960.

Current President Bassirou Diomaye Faye and Sonko were released from prison after the law took effect, and Sonko is now prime minister.

The former government and the security forces deny wrongdoing, although witnesses at the time told Reuters that security forces fired on crowds.

Rights groups and lawyers had called for the amnesty law to be repealed because it left families of the dead with no recourse for justice. 

The measure that passed on Wednesday by a vote of 126-20 does not repeal the law but instead removes amnesty for specific crimes including murder, torture and forced disappearance.

"Those guilty of serious crimes will be held accountable for their actions," said Oumar Sy, a member of Senegal's ruling Pastef party, during a debate over the law on Wednesday. 

But opposition lawmakers said the revised law shields protesters who they say were responsible for stoking violence and causing extensive damage.

"The proposed amendment before us is unfair and unacceptable," opposition MP Alassane Sall said.