Health officials have expressed alarm after huge crowds descended on Blackpool hours after it was excluded from coronavirus restrictions due to come into force this week. Day-trippers said they had “never seen Blackpool so busy” as people poured into the town over the weekend, with many reporting a lack of social distancing or face coverings. Gem Concannon, 36, from Northwich in Cheshire, said the town was “heaving”, adding: “Hardly anyone was wearing masks or social distancing. It was shocking. I’ve never seen it that busy before.” It came amid concern in government that the number of people following the rules has fallen sharply in recent months. Prof Chris Whitty, the chief medical officer for England, and Sir Patrick Vallance, the government’s chief scientific adviser, reportedly told Boris Johnson that compliance with the rules was among the worst in Europe. People who fail to self-isolate will be fined up to £10,000 from next week as Matt Hancock, the health secretary, warned that the government would be “increasingly stringent” on those not following the rules. Whitty and Vallance are said to have warned the prime minister that other countries, such as Germany and Sweden, had fared better than the UK at least partly because they had higher compliance with the rules. Footage on social media showed large crowds along Blackpool promenade on Saturday night and visitors reported queues for attractions, gridlocked traffic, little social distancing and few people wearing masks indoors. Some day-trippers said the town was “scarily rammed” and “packed to the rafters”, and that the promenade had been turned into a “Covid breeding ground”. One said: “Many people predicted it and so it happened, it seemed everyone came to Blackpool last night. The only time I’ve seen it busier is when the Red Arrows were on. Not much in the way of social distancing or masks”. Another said: “Blackpool will be in local lockdown in two weeks’ time.” From Tuesday, Blackpool will be the only area in a region of 5.9 million people not covered by restrictions on households mixing and a 10pm curfew on nightlife. The resort was not included in the restrictions because it has its own local authority boundaries and was not considered to be at a higher risk than other parts of the county. However, the decision, announced by the government on Friday, has prompted widespread confusion and concern as the town’s infection rate has doubled in the past fortnight and is now higher than some neighbouring areas that will be covered by the rules. Dr Arif Rajpura, Blackpool council’s director of public health, said the council would “ramp up” its messaging urging people to stick to the guidance following the large numbers drawn to the seaside town at the weekend. “Just because we weren’t included in the government restrictions across Lancashire doesn’t mean it’s a green light to do what we want. It’s even more crucial now that we try keep the virus levels as low as we can by following all of the guidance,” he said. Dr Sakthi Karunanithi, the director of public health for Lancashire county council, on Sunday said “don’t flock to Blackpool just because you can”. “My message to the residents of Lancashire is we need to look after each other, our family and our friends. The rates are rising in all parts of Lancashire. Just because Blackpool is not yet an area of intervention, or where these new rules apply, this guidance that has come out applies to all of Lancashire no matter who you are or where you live so you take it with you wherever you go.” The latest NHS Digital data, published on Sunday, shows Blackpool’s infection rate has risen to 57.5 cases for every 100,000 people, which is double the rate a fortnight earlier and nearly twice England’s average. It recorded 80 new cases in the week to 17 September. It is understood local leaders had expressed concern 1,000 spectators would be allowed into Blackpool’s Bloomfield Road stadium for the club’s League One match on Saturday as part of an English Football League (EFL) pilot. The game was chosen as one of 10 EFL matches in England where 1,000 fans would be allowed back into the ground. In Hull, another area chosen for the pilot, the trial was pulled at the last minute after the city’s public health team refused to grant approval, because of safety concerns. Lynn Williams, the leader of Blackpool council, said the town was busy at the weekend but that “people will always flock to coastal resorts in good weather”. She added: “Blackpool welcomes visitors but it is essential that people follow the ‘hands, face, space’ requirements.” Lancashire police said it would not order people not to visit Blackpool but said “people must stick to the regulations and follow social distancing to help us all return to some form of normality”.