A military unit in Madagascar says it is taking control of the country’s security forces as President Andry Rajoelina alleged an “attempt to seize power illegally” was under way.

The CAPSAT contingent, based in the Soanierana district on the outskirts of the capital, Antananarivo, joined thousands of antigovernment demonstrators on Saturday, calling on security forces to “refuse orders to shoot” and condemning police action taken to quell more than two weeks of youth-led protests that have rocked the Indian Ocean island.

The demonstration in the capital, Antananarivo, was one of the largest since the protest movement erupted on September 25, sparked by anger over power and water shortages.

Police used stun grenades and tear gas in attempts to disperse the crowds of several thousand people. Few left as soldiers from the CAPSAT contingent of administrative and technical officers entered the city in army vehicles to join the demonstrators.

They were greeted with cheers from protesters, who called out, “Thank you!” to the uniformed soldiers, some waving Madagascar flags.

On Sunday, Rajoelina released a statement saying: “An attempt to seize power illegally and by force, contrary to the Constitution and to democratic principles, is currently under way.”

“Dialogue is the only way forward and the only solution to the crisis currently facing the country,” he said while calling for unity.

Madagascar is one of the world’s poorest countries and has experienced frequent popular uprisings since its independence from France in 1960.

Faced with near-daily protests since September 25, Rajoelina dismissed his government on September 30 and appointed an army general as prime minister, but the move failed to quell the uprising.