The lure of holiday sunshine was too much for thousands of workers yesterday, who swapped suits for shorts and "pulled a sickie".

A specialist legal advisory service for businesses said more than 60 per cent of its calls were from employers concerned about absenteeism.

Britain's beaches recorded higher than normal numbers of visitors and those who did venture into the office found themselves able to find a seat on trains and buses that are usually packed.

With cool fronts expected to bring temperatures down to about 64F (18C) over the next few days, it seems that some workers could not resist taking advantage of the continuing hot spell, with temperatures reaching 77F (25C) in the Solent yesterday.

John Peel, of the Employment Law Advisory Service, said: "We have had hundreds of calls from employers saying they had staff calling in with all manner of excuses. One called in on Friday saying his cat needed an emergency operation. But when he made the same excuse three days later, his boss started to get suspicious.

"The weather has been so good, that people who wouldn't normally phone in sick have decided to try it on and give themselves a nice long weekend."

A survey found that absenteeism cost British business more than £13 billion last year and Mr Peel said the firm had now advised several employers that they were legally -entitled to sack staff they -suspected of being dishonest.

"Quite a few people have been sacked as a result. Some of them had quite high-profile roles where this kind of behaviour will not be tolerated. However, we advise most firms to take a softly, softly approach with this kind of thing," he added.

Brighton beach was busy yesterday with people "of working age", said a spokesman for the city council, while along the coast at Bournemouth an estimated 20,000 people packed on to the sand.

"It is exceptionally busy for a weekday," said Jo Mountain, PR manager from Bournemouth Tourism. "We've had a record-breaking Easter, an amazing weekend after that, and it is continuing. The summer season seems to have started already.

"As for whether people are here because they have pulled a sickie from work, I couldn't say, but the whole resort is benefiting from the extra people."

Hire of deck chairs soared by 2,000 per cent over the Easter weekend compared to the same week last year, she said.

A spokesman for the Met Office said recent temperatures were about 10C above average for the time of year.

Among those relieved by the falling temperature will be runners in the London Marathon this weekend. The Rotterdam Marathon had to be halted on Sunday when at least 26 runners were taken to hospital because of the heat.

A spokesman for the London race said organisers were monitoring the forecasts and were ready with extra water, medical supplies and personnel should the need arise.