London- A wildcat strike by British Airways ground staff at London”s Heathrow airport halted BA flights and caused serious delays to tens of thousands of passengers Friday, DPA reported.

BA cancelled all flights to and from the airport – its main hub – until 6 p.m. Friday evening and urged passengers not to report for check-in.

One report suggested the strike could go on through the weekend, costing the airline 10 million pounds (18 million dollars) a day.

Some 70,000 passengers were said to have been affected by the strike, which began Thursday evening when BA baggage handlers and other ground staff walked off the job in sympathy with almost 800 sacked catering workers from Gate Gourmet, which supplies BA”s onboard food.

Gate Gourmet said its workers had been given two hours to decide whether to work normally before they were sacked Wednesday in a dispute over working practices.

Heathrow managing director Mick Temple said efforts were being made to minimize disruption to the flights of other airlines.

The airport erected a large marquee to cope with the stranded passengers. Some 2,000 people were handed blankets and spent the night at the airport, while others were accommodated in nearby hotels.

BA said that almost 100 aircraft and 1,000 pilots and cabin crew were in the wrong places around the world because of the impact of the strike.