A major UK entertainment operator has been fined an historic £5million over a “catastrophic failure” to meet basic health and safety regulations.

Merlin Attractions, operator of Alton Towers amusement park in Staffordshire, admitted to such failings in court earlier this week.

The proceedings related to a “needless and avoidable accident” in June 2015, which saw 18 people “injured to various degrees,” a court was told.

Two then-teenage girls, aged 17 and 19, respectively, each lost a leg in the accident – a “catastrophic” rollercoaster crash which has been likened to a 90mph car collision.

The accident saw an 18-person carriage plough into an empty cart, which was stationary on the track of the park’s Smiler rollercoaster.

A court heard that the incident occurred after an engineer “felt pressured” to get the rollercoaster back into action following a known fault which was brought to his attention.

“A computer control system was reset, having been overridden to address a fault”.

Riders experienced “great pain and distress” for up to five hours following the collision – and the first 999 call to emergency services was not made until at least 17 minutes after the crash, a court was told.

Judge Michael Chambers QC said that the “obvious shambles of what occurred” could have been “easily avoided” if Alton Towers had put in place a suitable system to deal with ride faults and carried out proper risk assessments.

“This was a needless and avoidable accident in which those injured were fortunate not to have been killed or bled to death,” he said.

Sentencing Merlin Entertainment, Judge Michael Chambers QC added that “human error was not the cause” of the incident.

He said: “The defendant now accepts the prosecution case that the underlying fault was an absence of a structured and considered system not that of individuals’ efforts, doing their best within a flawed system”.

Merlin Entertainment was ordered to pay an historic £5m fine.