Police have made an emergency declaration under the Public Safety Preservation Act (PSPA), due to an on-going incident in Kirwan this afternoon.
Shortly after 1pm, police attended a Gill Street property in relation to a disturbance.
Upon arrival, officers began negotiations with a man inside the residence alone, believed to be armed.
An emergency situation was declared around 2.30pm, with boundaries encompassing Frank Street, Farrell Street, Hall Street and Joyce Street.
Members of the public are advised to avoid the area and those within the exclusion zone are asked to remain indoors until further notice.
Traffic diversions are in place for Gill Street.