Workers at a British factory making French fries were evacuated two days running last week after bomb parts turned up in potatoes imported from France and Belgium, the site of battles in World War 1 and 2.
The Scarborough plant, owned by Canada's McCain Foods, the world's largest producer of frozen fries, was emptied on Friday after a worker spotted a shell tip among the potatoes as they were being cleaned for slicing.
"The police were called and the bomb squad advised a 100m exclusion zone should be set up," said a McCain spokesperson.
On Saturday, an entire hand grenade was discovered in the potatoes and the plant in northern England was evacuated again.
A spokesperson for North Yorkshire police said "The army took the device away and blew it up in a controlled explosion in a field nearby."
The Scarborough plant was opened in 1969 and uses 1 400 tons of potatoes a week. Production is back to normal.
McCain's Whittlesey plant near Peterborough in eastern England also has also been evacuated several times this year after World War 2 ordnance was found in batches of potatoes.
"Occasionally during the use of imported potatoes from Belgium and northern France, ordnance debris from the World War 1 and 2 is found," said the firm.