Thousands demand resignation of Colombia's chief prosecutor

Thousands of Colombians have joined protests in cities across the country to demand the resignation of the country's chief prosecutor, Nestor Humberto Martinez.

Protesters at a rally in Bogota could be seen tearing down and then burning a flag outside his office.

Some held placards accusing him of corruption.

Martinez is a crucial U.S. ally in the war on drugs, however he is accused by his critics of obstructing an investigation linking Colombian politicians and business groups with Brazilian construction firm Odebrecht.