French meat supplier Spanghero’s president, Barthelemy Aguerre, talks to journalists in Castelnaudary on Friday. Veterinary and sanitary inspectors continued to research the firm. Photograph: Remy Gabalda/AFP/Getty Images

Rogue horsemeat was on Friday identified at school dinners and hospital meals for the primary time as officials from the Food Standards Agency confirmed new police raids on three more food companies.

Official tests of processed beef dishes sold in supermarkets revealed that 2% of these tested up to now had found horsemeat but as those results were being announced the scandal was confirmed to have spread to both public sector caters and major restaurant chains owned by Whitbread.

In Lancashire cottage pies destined for 47 schools around the county were withdrawn after testing positive for horsemeat. It was not clear how long the tainted food have been at the menu or what number pupils can have eaten it.

In Northern Ireland a variety of burgers bound for hospitals were withdrawn after officials confirmed they contained equine DNA and food giant Compass, which provides over 7000 sites within the UK and Ireland including schools and hospitals, said a burger product it supplied to 2 colleges and a small choice of offices in Northern Ireland and the Republic of eire had tested positive.

As the horsemeat scandal continued into its sixth week, it was revealed that:

• The Food Standards Agency’s first wave of test results from retailers found 2% of 2500 samples of processed beef products contained greater than 1% horsemeat, although experts warned the testing “didn’t get to the foundation of the scandal.” The tainted samples were from seven products that had already been withdrawn, including Findus lasagne and Tesco burgers. None tested positive for the drug phenylbutazone – or “bute” – used on horses but banned from entering the food chain.

• Pub and hotel group Whitbread, which owns Premier Inn, Beefeater Grill and Brewers Fayre, confirmed horse DNA have been present in meat lasagnes and beefburgers.

• Officials on the department of health said it had written to NHS hospitals and “social care providers” asking them to hold out “suitable checking regimes at the authenticity of food.”

• Sheffield council has suspended using all processed meat in schools and Staffordshire council said it had taken beef off school menus as a “precaution.”

• The ecu Union decided to to begin testing for the presence of unlabelled horsemeat in foods around the Continent. Tests can also be applied for the presence of residues bute. In France veterinary and sanitary inspectors continued to enquire Spanghero, a meat processing and wholesale firm, accused by the govt of fraudulently stamping the label “beef” on around 750 tonnes of inexpensive horse meat.

On Friday morning officials from the Food Standards Agency and police achieved three raids on suspect food companies – one in Hull and two in Tottenham. A spokesman confirmed computers and documentary evidence was seized, in addition to meat samples. The raids follow the targeting of a slaughter house in West Yorkshire and a meat plant in Wales as portion of the broader investigation.

Parents in Lancashire were told cottage pies on school menus were found to have horsemeat in them on Friday. The council said just a small collection of pupils were exposed to the food and insisted there has been no health risk.

County councillor Susie Charles said: “Relatively few schools in Lancashire use this actual product but our priority is to produce absolute assurance that meals contain what the label says – having discovered this one doesn’t, we haven’t any hesitation in removing it from menus.”

Other local authorities and catering companies who provide school food are understood to be undertaking similar tests but official testing of public sector caterers aren’t due until later int he spring.

The British Hospitality Association which represents lots of the major providers of meals to colleges said its members were testing their minced beef products in agreement with the Food Standards Agency (FSA) and government, although they said they were still anticipating the “overwhelming majority” of results to come back through because of a backlog on the testing laboritories.

The Department of Health said it had written to NHS providers urging them to check all relevant food and expected the implications to be made public next week.

“It’s unacceptable that any one have to have been eating meat that is not what it says at the label,” said a spokesman. “However, we want to reassure patients that although horsemeat is located in hospital food supplies there’s nothing to signify a security risk to those that could have eaten the goods.”

Catherine Brown, FSA chief executive, said the outcomes published on Friday following tests completed by food retailers confirmed the “vast majority of beef products on this country don’t contain horse meat.”

But the implications only account for roughly 1 / 4 of all of the products eaten by consumers and didn’t seek for trace contamination, a choice described as “pragmatic” by the FSA. The consequences also didn’t include the positive tests uncovered by Whitbread and Compass. “Clearly, this can be a fast changing picture,” said Brown, who said more test results will be revealed next Friday.

Mark Woolfe, who led the FSA’s surveillance for a decade as much as 2009 said the testing didn’t get to the basis of the scandal for the reason that problems inside the supply chain that resulted in the contamination within the UK were still largely unknown. “The FSA and the industry were remarkably silent on what went wrong within the supply chain of the firms that were found right at the beginning of the investigation in Ireland,” he told the Guardian. “They’ve got had four weeks to determine. Investigating the provision chain is a far more efficient approach to solve the issue than end product testing.”

Last night our surroundings secretary Owen Paterson said the “food businesses” still had lots of work to do. “They should move quickly to finish these tests and that they have to show their customers they’ve taken the ideal steps to verify this does not happen again.”

But Mary Creagh, Labour’s shadow environment secretary, said the govt had repeatedly did not get on top of the placement.

“Ministers ought to stop hiding behind the retailers and food industry and take decisive action to get a grip in this scandal now. They ought to order the FSA to hurry up its testing.”