Rio de Janeiro  - A grenade explosion left 10 people injured at a funk dance in a Rio de Janeiro slum early Monday, the authorities said.

The blast happened as the audience was leaving a club at around 3 am in the favela (slum) of Antares, in the western Rio neighbourhood of Santa Cruz.

Rio military police said the grenade was launched from a moving vehicle. The motives for the attack and the identity of the perpetrators were not immediately known. Five of the injured were minors. (dpa)