The authorities have closed down the M2 motorway in both directions until at least daylight on Tuesday due to a crash, according to Transport NI.
The crash involving a number of vehicles had unfolded some time around 8.40pm on Monday.
The PSNI described the incident as “serious”.
Some details from the emergency services were unclear; it was initially believed to be on the west-bound lane of the motorway between Sandyknowes and Templepatrick.
However, a source later suggested that it could have occurred just beyond Templepatrick.
Both lanes were shut down.
Transport NI said late on Monday that the motorway would remain closed in both directions between these areas until at least daylight on Tuesday morning.
Police were in attendance.
Three ambulance crews were dispatched, but one was stood down en route.
It is thought the fire brigade may also have been summoned.
The ambulance service said one person was taken to Antrim Area Hospital, condition unknown.
However, the Northern Health Trust (which runs the hospital) said they believed no patient had yet arrived, when the News Letter rang shortly after 11pm.