Tear gas streams through the streets of La Paz

Riot police were called in to clear protesters from the street, launching tear gas at the crowd. Demonstrators responded by throwing tear gas canisters back at police.

Morales won last month's vote with a lead of just over 10 points over Carlos Mesa, his nearest rival, giving him an outright win. The victory, avoiding a second-round runoff vote, was marred by a near 24-hour halt in the count, which, when resumed, showed a sharp and unexplained shift in Morales' favour.

The Organisation of American States (OAS) is doing a count audit, expected to be completed before the middle of the month. It raised concerns after the count was halted and has recommended a second-round vote.

But critics of Morales have not been placated by the audit, calling for Morales to step down.