Zimbabwe's main opposition party, the Movement for Democratic Change (MDC), has said three people were shot at its headquarters in the capital, Harare.
The MDC said a lawyer who rents an office in the same building opened fire on two security guards and a party supporter.
However, a Zimbabwe police spokesman, Wayne Bvudzijena, disputed the MDC's version of events, saying the lawyer opened fire only after he was shot at.
From the newsroom of the BBC World Service