There are emergency exits on Ryanair planes.

Full power to the police for getting them off the plane quickly, and breaking into the airport.

However I was under the impression that the police were allowed to check passports and let people in the country. On that flight of be very surprised of there was more than a handful of non eu citizens.

Indeed g4s were approving people to fly on a domestic flight last night at lhr, based on their opinion of a driving license or passport photo.

However these things happen. How soon we forget
http://m.bbc.co.uk/news/uk-22717377 - British Airways passengers sleep at Venice airport

€250 compensation and something on top of that (Ryanair Avios?) for the illegal treatment.

Or you could try a criminal charge against the pilot.