By Abraham Achirga
ABUJA (Reuters) - Nigerian police opened fire and shot tear gas at Shi'ite Muslim protesters in the capital of Abuja on Tuesday, according to a Reuters witness, the second straight day of violence involving the group.
Soldiers on Monday opened fire on a march in Abuja by members of the Islamic Movement of Nigeria (IMN) which is trying to secure the release of its leader Ibrahim Zakzaky.
IMN protesters say the army killed at least 18 of their number in Monday's shootings though the military has said only three people died and four soldiers were injured.
Police on Tuesday attempted to stop hundreds of IMN members as they headed towards the centre of Abuja, where most government buildings and the presidency are located.
When marchers refused to turn back, police fired tear gas on the crowd. The protesters responded by hurling rocks, and the police opened fire, according to the Reuters witness.
At least one IMN member was wounded by the gunfire, the witness added.
(Reporting by Abraham Achirga; Writing by Paul Carsten; Editing by Richard Balmforth)