CONAKRY, Guinea (AP) -- Chaos erupted at a soccer game in Guinea after fans protested a referee's call and thousands of panicked spectators tried to flee the stadium, leaving at least 56 people dead in the West African nation, officials and witnesses said Monday.

Amid the confusion, security forces used tear gas, local news website Media Guinea reported. Many of the dead were crushed as they tried to escape through the stadium gates, a journalist covering the game for a local sports website told The Associated Press.

"The gates, that's where the stampede happened," said Cisse Lancine, who got away by climbing over one of the stadium walls. "I was saved because I did not rush towards the exit."

The world's latest sports crowd disaster unfurled Sunday in the second-largest city in a military-run nation where information is sparse and government-controlled at the best of times. It was not immediately clear how much the death toll could grow.

Lancine said between 20,000 and 30,000 people were present at the Third of April stadium to watch the local Labe and Nzerekore teams compete in the final of the first national tournament honoring military leader Mamadi Doumbouya.

Checkpoints were set up Monday throughout Nzerekore, a city of about 200,000 that was at a standstill as soldiers guarded the hospital where victims were being treated. Most shops were closed.

Video, apparently from the scene, showed shouting fans protesting the refereeing. People ran as they tried to escape the stadium, many of them jumping the high fence.

"Supporters threw stones. This is why the security services used tear gas," reported Media Guinea, which also wrote that several of the dead were children and some of the injured were in critical condition.

The footage showed people lying on the floor of a hospital as members of a crowd helped the wounded.

Enock Loua, a resident of Nzerekore, learned over the phone that his niece Aline Olivier had been killed.

"We have a hard time realizing what happened to us, it is as if the sky has fallen on our heads," Loua told The Associated Press.

Authorities are trying to establish who was responsible, Prime Minister Amadou Oury Bah said on national television.

The National Alliance for Alternation and Democracy opposition coalition said the tournament was organized to drum up support for Doumbouya's "illegal and inappropriate" political ambitions.

Doumbouya, who ousted then-President Alpha Conde in 2021, has been eyeing a possible run for the presidential election, for which the date has not been set. The transition charter put in place by his own regime does not allow him to run.

Guinea is one of a number of West African countries -- including Mali, Niger and Burkina Faso -- where the military has taken power and delayed a return to civilian rule.

Doumbouya said he was preventing the country from slipping into chaos and chastised the previous government for broken promises. He has, however, been criticized for not meeting the expectations that he raised.

Guinea's leader announced three days of national mourning starting on Tuesday, in a presidential decree read on national television.