Police in Malawi fired tear gas to disperse thousands of protesters on Tuesday who had gathered to show solidarity with an activist as he handed himself in at a police station.

Timothy Mtambo was wanted by the police after his organisation, Human Rights Defenders Coalition, called for demonstrations to put pressure on President Peter Mutharika to replace the electoral commission.

Two of his colleagues were arrested on Sunday.

In February, the constitutional court annulled President Mutharika's victory in last year's election due to widespread irregularities.

A re-run of the election is to be held later this year but it is not clear if the president will agree with parliament's recommendation to replace the senior officials at the electoral commission.