The police officer who shot and killed an unarmed black teenager last weekend sparking race riots was injured in the incident, a police chief has said. The officer, who has not been named, shot 18-year-old Michael Brown dead in Ferguson, Missouri but is said to have been hospitalized himself after the shooting, suggesting there was a struggle. Ferguson Police Chief Thomas Jackson said the unidentified officer was treated for swelling on the side of his face after the incident on Saturday. Scroll down for video Stand-off: Riot police watch as protests over Michael Brown's shooting continue for a four successive night
@highlight
Unidentified officer hospitalized with 'facial swelling' after shooting
@highlight
Police say there was a 'struggle' before Brown, 18, was shot dead
@highlight
Riots in Ferguson, Missouri continue for a fourth successive night
@highlight
Police throw smoke bombs and tear gas as protestors ignore curfew
@placeholder urged protesters to rally only in daylight hours, but more than 500 people broke the curfew last night, chanting: 'Hands up!