Attackers hurled a grenade Monday in the Burundian capital Bujumbura close to a polling station, a few hours after voting started in controversial polls, an AFP photographer said.

The grenade attack, the latest of several overnight before polls opened, took place around 9:00 am (0700 GMT), few hundred metres from the polling centre in the capital's Musaga district. It was not immediately clear if there were any casualties.