Alton Towers Resort has apologised to all of the people who were affected by the roller coaster accident at the park today which left four people seriously injured.
Nick Varney, chief executive of Merlin Entertainments, which runs the resort, described the collision, in which two men aged 27 and 18 and two females aged 19 and 17 suffered serious leg injuries, as "a terrible incident."
This has been a terrible incident and a devastating day for everyone here.
I would like to express my sincerest regret and apology to everyone who suffered injury and distress today and to their families.
The safety of our visitors is our primary concern. The park will remain closed until we understand better the cause of this dreadful incident.I would like to thank the emergency services for their swift and effective response today - they were outstanding.
A full investigation is now under way and we will continue to work closely with the emergency services and the Health and Safety Executive.
The boyfriend of a teenager who had her leg amputated after a rollercoaster crash says the theme park should have shut down the ride.
Details of the rides that have been halted and what to do if you have tickets for Alton Towers.
A man who witnessed the rollercoaster crash at Alton Towers told ITV News he raised concerns about a carriage on the track but was ignored.