A controversial refereeing decision sparked violence and a crush at a soccer match in southeast Guinea, killing 56 people, according to a provisional toll, the government said on Monday, as a witness described scenes of chaos.

The fatalities occurred during the final of a tournament in honour of Guinea's military leader Mamady Doumbouya at a stadium in Nzerekore, one of the West African nation's largest cities.

Fans threw stones, triggering panic and a crush, the government statement said, promising an investigation.

A witness, who had attended the match, said a disputed red card in the 82nd minute of the match kicked off the violence.

"The stone throwing started and the police joined in, firing tear gas. In the rush and scramble that followed, I saw people fall to the ground, girls and children trampled underfoot. It was horrible," Amara Conde told Reuters by phone.

The crowd rushed to leave, leading to a dangerous scrum at the exits, a police source said.

A video authenticated by Reuters showed dozens of people scrambling over high walls to escape.

Ousted President Alpha Conde said the event had been badly organised at an uneasy time for the country, which is waiting for Doumbouya to hold promised elections after he seized power in a 2021 coup.

"In a context where the country is already marked by tensions and restrictions, this tragedy highlights the dangers of irresponsible organisation," Conde said in a statement.

Speaking on condition of anonymity, an official from the city's administration said many victims were minors caught in the turmoil after police started firing tear gas. The official described scenes of confusion and chaos with parents retrieving bodies before they were officially counted.

Videos and pictures shared online showed victims lined up on the ground. In one video, over a dozen inert bodies could be seen, several of them children.

Reuters was not immediately able to verify that footage.

BROKEN PROMISES

Opposition group National Alliance for Change and Democracy said authorities bore responsibility for organising tournaments to bolster political support for Doumbouya in contravention of a transition charter prior to the long awaited presidential election.

There was no immediate response from the military junta to that accusation.

Doumbouya's junta proposed a two-year transition to elections from 2022 after negotiating with West Africa's political and economic bloc, but it has shown little sign of moving to organise a vote, stoking public frustration and occasional deadly protests.

On Monday, Human Rights Watch accused the military authorities of cracking down on the opposition, media, and peaceful dissent, and failing to keep their promises to restore civilian rule by December 2024.

It said in a report that security forces had used excessive force, including tear gas and gunfire, against protesters.

There was no immediate response from the junta to the HRW allegations.

Recent decades have seen a number of deadly disasters in soccer stadiums. The Confederation of African Football has been working with soccer's world governing body FIFA to tackle dangerous overcrowding and other safety issues in African stadiums.