Police have used a Taser gun on a man who was trying to stop traffic with a knife.
It happened on the Ligoniel Road in north Belfast shortly after 7am on Monday.
Police said the Taser was fired by a specialist firearms officer in order to "prevent harm to the male himself or anyone else".
The man has been arrested and is currently in custody.
A statement from the PSNI said: "The Police Ombudsman of Northern Ireland has been informed in line with agreed PSNI protocols".