Counter-terrorist experts said that India would have been selected for the latest spectacular "probably because that's where al Qaeda has sufficient resources to carry out an attack on this scale." They don't choose for the sake of it, they look to see where they have the greatest capability and then order an attack," a counter-terror expert told The Times.
They said the key to this latest attack was the search by the armed terrorists for American and British passport holders.
With a reported 40 Britons held hostage, the terrorists have the upper hand. The counter-terrorist sources said targeting Mumbai's most luxurious hotels and a crowded railway station had all the hallmarks of an al-Qaeda operation.
Mumbai has been targeted before when 180 people died during a bomb attack on several trains at a city railway station in 2006, but that incident was put down to militants, not al Qaeda, and the Indian government then suspected that the attackers had links to Pakistan's intelligence service, the ISI.
Wednesday's attacks, however, involving the taking of Western hostages made it more likely that the operation's masterminds were from the core leadership of al-Qaeda, which is based in the lawless tribal regions close to the Pakistan-Afghanistan border, they said.
They also said that in recent weeks they were expecting an al Qaeda-type spectacular terrorist attack between the end of President George Bush's administration and the succession of Barack Obama.
They said Osama bin Laden's terror outfit might be plotting an attack "to grab headlines" before Obama takes over on January 20.
The attacks on Western targets in Bali in 2002 when al Qaeda-linked terrorists planted bombs in tourist-favoured restaurants and clubs was another example where the group switched its resources to achieve maximum impact.
The Americans have been expecting an atrocity partly because of the recent CIA success in eliminating figures in al-Qaeda, using Predator unmanned drones, firing Hellfire missiles at hideouts in the tribal regions of Pakistan. About a dozen al-Qaeda figures have been killed this year.
Other sources said India was the home of a complicated network of terrorists and it might be too early to jump to the conclusion that it was an al-Qaeda operation.
Some said the attacks in Mumbai are traditionally the way al Qaeda works. The leadership decides an attack should take place and leaves its franchise operators to decide how best to carry it out. Many of the gunmen appeared to be young but they also seemed confident, suggesting that they were well trained.
As the unprecedented scale of the attacks became clear last night, it looked to be the most co-ordinated terrorist operation since the targeting of the Twin Towers in New York in 2001.
Dozens of gunmen were involved in up to 19 different attacks, although the main focus seemed to be the taking of foreign hostages and detaining them in two of Bombay's most prestigious hotels.
Judging by the apparent cockiness of at least one of the gunmen caught looking into television cameras, these terrorists were clearly prepared to die for their cause.
al Qaeda as an organisation has proved in the past that it has the capability to coordinate multiple attacks.