President Evo Morales of Bolivia has narrowly lost a referendum to allow him to stand for a fourth term in office, exit polls suggest.
One poll suggests 52.3% voted against the proposal to amend the constitution, while another suggests it was 51%.
However, Mr Morales’s deputy has predicted Bolivia’s first head of state of indigenous origin could still win, as official results trickle in.
The constitution change would have let Mr Morales remain in power until 2025.
Opposition supporters have been celebrating the referendum result in parts of the main city, La Paz.
Mr Morales, an indigenous Aymara and former coca leaf producer, took office in January 2006.
He is still a popular leader and the economy has grown steadily over the past decade, the BBC’s Americas Editor, Leonardo Rocha, reports.
However, many thought Evo Morales should not be allowed to serve 19 consecutive years as president, our editor adds.
Appeal for caution
Opposition leader Samuel Doria Medina urged Mr Morales to “recognise the results” and focus on solving Bolivia’s problems in his remaining time in office instead of trying to run for another term.
However Vice President Alvaro Garcia Linera said the results so far were a “technical tie”.
He urged people to wait for the official results and said any celebrations by the opposition were premature.
“Opinion polls, especially exit polls, make mistakes,” he told reporters.
“They don’t take into account the vote abroad. They don’t go to the more remote locations, where there is more support for our socialist movement.
“It’s highly likely that the numbers shown by the opinion polls will be very different from the reality.”

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