Authorities in Tanzania are facing international scrutiny over deadly crackdowns on post-election protests, with the main opposition party, Chadema, claiming security forces have secretly disposed of hundreds of bodies.

Protests erupted after the Oct. 29 election, which President Samia Suluhu Hassan won with over 97% of the vote amid low turnout and barred opposition candidates.

Security forces used live bullets and tear gas, enforcing a nationwide curfew, and Human Rights Watch condemned the use of lethal force.

Reports from the U.K., Norway, Canada, the Catholic Church, and local legal groups suggest that over 1,000 people may have been killed, particularly in politically active regions, the AP has reported.

Chadema officials allege that many victims, including at least 400 in the Mbeya region, are being secretly dumped by authorities to conceal the scale of the killings.