An engineer has repaid £2 million mistakenly paid to him by his employer.
The employee opened his pay slip to find bosses had given him the sum reported to be 1,000 times his normal salary of £2,000.
Bosses at Alcoa Howmet, in Exeter, Devon, admitted they paid a worker a "significant" sum last week following an error.
The mystery worker is said to have been stunned at the massive windfall. But, the engineer - who makes turbine blades - immediately told bosses he would return the money.
Alcoa spokesman Jasper Van Zon would not confirm the exact amount involved, but the sum is reported to be £2 million.
He said: "The amount of money is a matter between us and the employee. I can say the sum of money involved was a significant amount.
"We are very happy that the employee acted so quickly, that the person acted in such an honest way. It showed a lot of integrity.
"It's a very good thing to see when an employee reports this kind of mistake so quickly. It is a good example of the quality of people we have at our company.
He added although they are very happy with the employee's behaviour the matter was being taken seriously and they would be investigating the matter.
The company believes the overpayment would have been traced within days and the employee would have been asked to repay the money if he had not done so voluntarily.