A senior UDA commander was one of two men arrested under the Prevention of Terrorism Act in the north today, a security source confirmed tonight.
The source said Jackie McDonald was being questioned at the terrorist holding centre in Antrim in relation to serious crime in the Belfast area.
McDonald, a former loyalist prisoner, and a second man were picked up by detectives this morning.
They can be held for up to 24 hours before police have to seek an extension to their custody.
PA