Most of the 750,000 Britons who visit India every year have a “trouble-free” stay, according to the Foreign and Commonwealth Office’s website, but last night its advice to those in Bombay was “to stay indoors until local authorities advise that it is safe to go outside”.

The England cricket team’s tour of the country hung in the balance and the Middlesex county side, who were scheduled to fly to Bombay this morning for the inaugural Twenty20 Champions League, were told that the tournament was being rearranged.

“They’re trying to change the venues,” Shaun Udal, the Middlesex captain, told The Times. “It’s definitely not happening in Mumbai, we’ve just had our flights cancelled. They’re trying to reorganise it in Bangalore and keep the dates the same, but I’ll be very surprised if that happens. We’ve been told not to travel.”

Foreign cricket fans in Bombay for the tournament, which begins next week, would be likely to stay in the south of the city where most of the attacks took place.

The Brabourne Stadium, where three Champions League matches and England’s second Test against India were scheduled to be played, is very close to the hotels that have been attacked.

Middlesex, like the England team next month, were to stay at the Taj Mahal Palace hotel.

Last night the England side were miles away in Cuttack, on the east coast, and it remained unclear whether the tour would continue.

The curtailment of the cricket tour would be a further blow for the Indian tourism industry, which has already suffered from a string of terrorist attacks since July 2006.

These attacks, often in major tourist destinations such as Delhi and Jaipur, meant that even before yesterday the threat from terrorism across India was assessed by the Foreign Office to be “high”.

Britons were advised to “exercise particular caution” when close to important government buildings, but also in public places such as hotels and on public transport — both of which were targets yesterday.

Although Bombay is not one of the biggest tourist destinations in India, according to the Association of British Travel Agents, all sorts of British tourists do flow through the city, which is used as a connection point for those flocking to the beaches and parties of Goa, as well as those travellling elsewhere in India.

It is also a key port of call for many foreign business travellers.

Bombay is the centre of India’s thriving film industry and is also one of the key financial hubs in a country whose economy is growing rapidly.

Sajjad Karim, the Conservative MEP who was caught up in gunfire at the Taj Mahal Palace hotel has been visiting the city as part of a trade delegation.

Every day 600 people fly into the city from Heathrow on one of the two British Airways flights alone.

The Foreign Office last night issued an emergency number for people concerned about friends or relatives: 020-7008 0000.

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