PSNI detectives have arrested a man in connection with the murder of leading loyalist John Boreland.
The 42-year-old suspect was arrested in the city earlier.
Mr Boreland - who was a member of the UDA - was gunned down near his home in north Belfast on Sunday night.
It has led to fears of violent reprisals in the city.
The PSNI are maintaining an increased presence on the streets of Belfast in an effort to prevent further bloodshed.
Police say they had warned Mr Boreland about his safety in recent weeks.