A remote-controlled helicopter carrying drugs deliberately crash-landed at Dublin's Wheatfield Prison yesterday.

It's understood a prisoner was awaiting the delivery - and swallowed some.

He's now being held at a secure location on-site. Gardaí are investigating the incident.

The Prison Service isn't offering any public comments on the security breach at Wheatfield Prison yesterday morning - but privately sources have confirmed the story.

A remote controlled helicopter - carrying drugs - crash-landed in the yard - where prisoners quickly surrounded it.

One of them is believed to have intercepted some of the substances from the crashed drone and swallowed them.

It's understood he's now being held until the drugs are produced.

The prison service says the incident is now firmly a Garda matter - and investigations are continuing.