Scores of people including children have been rescued after being stranded on a ride at Chessington World Of Adventures.
All people were safely back on the ground four hours after they became trapped and had reportedly suffered no injuries.
The London Fire Brigade was called to the theme park shortly after 5pm on Sunday.
By that time, the 39 people on board the Rameses Revenge ride had already spent an hour suspended 20ft in the air, witnesses said.
In a statement, Chessington said the Rameses Revenge experienced a "technical problem" at 4.06pm.
"This resulted in the automatic fail-safe system bringing the ride to a controlled stop. Experienced resort staff were on site immediately to assist with guest care."
"No guests were injured in the incident," the statement went on to say.
"A small number of people were on the ride at the time and the resort's engineers worked with the emergency services implementing well-rehearsed procedures to ensure their comfort and safe removal from the ride.
"We are very sorry for any discomfort our guests experienced during the delay."
A spokesman confirmed the attraction would re-open today.
Justin Coo of London Fire Brigade told Sky News that many of those trapped were "agitated and stressed".
He said children as young as eight were likely to have been on it but - as there was a minimum height requirement of 1.4 metres - there were not thought to be any aged younger.
Passenger Mairead Cashin, 13, told Sky News of the moment passengers started realising something was wrong.
"After five minutes of stop, we were like, 'Oh My God, something's up'. Everyone kept announcing things but we couldn't hear we were so high up.
"So we were really panicking, we have no idea what's going on."
Sky reporter Stephen Douglas said Rameses Revenge is one of the star attractions at the theme park.
"It normally takes people very up high into the air, and what seems to have happened today is that about 30 seconds into the ride - when it was just getting started, only about 20 ft in the air - it suddenly jammed.
"It stayed suspended in the air for the next four hours until the fire services came and cut them out."
Catherine Cashin spoke to Sky News while her daughter Mairead was still on the ride. She said the children were brought down to safety "in priority order".
She added: "It is very concerning because they were stuck and all the electrics failed.
"They were on the ride for 90 minutes before the fire and rescue service came out to them."