Thrill-seekers have been left stuck on a rollercoaster at Alton Towers which previously crashed seriously injuring five people.
The theme park visitors were on the Smiler when there was a "temporary stoppage" but nobody was injured, a spokeswoman said.
The £18 million ride at the Staffordshire attraction smashed into another carriage on June 2 2015.
Five people were seriously injured in the incident and an investigation found that a computer block stopping the ride because of a stationary car on the track had been over-ridden by staff, causing the crash.
Vicky Balch, 20, from Leyland suffered horrific injuries when the Smiler rollercoaster crashed last summer.
Merlin Attractions Operations Ltd admitted a breach of health and safety rules over the incident.
An Alton Towers spokeswoman said: "On Thursday September 1, Alton Towers Resort stopped The Smiler to investigate claims a piece of debris that had fallen from a carriage.
"At no time were guests on the ride at any risk and all were safely removed from the ride promptly by staff in line with our comprehensive standard procedures.
"As the health and safety of our guests is our priority, the ride will remain closed whilst the Resort's technical team investigate the matter."
The theme park said there were 32 people on the ride when the incident happened.