Cottage pies containing horsemeat was served up to Lancashire schoolchildren, tests have indicated.
Up to 47 schools in Lancashire unknowingly fed young pupils horsemeat in cottage pies. Tests on the meals found traces of horse DNA, Lancashire County Council said.
The pies were removed from menus in another sign of a widening collapse in confidence in the food on Britain's plates.
A council spokesman said: "The provisional results of the tests on a preprepared cottage pie from an external supplier have been passed onto the Food Standards Agency."
Cottage pie has also been banned by Staffordshire County Council from 350 schools, over fears about its meat content.
The move was a precautionary measure, said a senior councillor.
Staffordshire council cabinet member for the environment, Mark Winningham, said: "We have every confidence in our suppliers.
"However, while this story continues to be in the news, it seemed sensible to offer an alternative meal where beef was not farm-assured and sourced in the UK.
"We are committed to promoting and using local produce as much as possible and are expanding a pilot scheme in schools where only meat from Staffordshire is used.
"While there is absolutely no suggestion that there is any problem with any of the beef supplied, we wanted to take a belt-and-braces approach."
In Northern Ireland, steak burgers were scratched from from school menus.
The deepening horsemeat crisis shows no signs of abating, with a poll by GMI showing that 36 percent of people fear buying processed meat because they do not trust what labels say.
Tests are being carried by the Food Standards Agency on food served in schools and hospitals.
An ICM poll found that 45 percent of shoppers will avoid buying meat from big-name supermarkets including Asda, Tesco, Iceland, Aldi and Lidl.
The revelations from Lancashire emerged as a Whitbread pub and restaurant admitted that horsemeat had been served up to diners in its beef lasagne and burgers.
The government insists that the still-unfolding scandal is about fraudulent labelling and is not a safety issue.