At least 20 children have died in a fire in the central Guyanese mining town of Mahdia, officials say.
The fire broke out just after midnight on Monday, engulfing a secondary school dormitory and trapping students.
Emergency services are struggling to contain the fire because of bad weather conditions, the government says.
Several more people have been injured and some are being prepared for evacuation to the capital, Georgetown, where a special centre has been set up.
"This is a major disaster. It is horrible, it is painful," said Guyanese President Irfaan Ali.
Mr Ali was quoted by AFP as saying that, as well as medical teams stationed at the airport, Georgetown's two major hospitals would be prepared "so that every single child who requires attention be given the best possible opportunity to get that attention".
Home Affairs Minister Robeson Benn is at the scene of the disaster, and the prime minister and other government officials are on their way there.
"It is with heavy heart and pain that the Cabinet is being briefed and kept updated on a horrific fire at the dormitory in Mahdia. All efforts are being made to have a full-scale medical evacuation-supported response," the government's Department of Public Information said in a statement.
Guyana is located between Venezuela and Suriname on the northern coast of South America.