NEW DELHI: The US embassy in India warned American citizens on Friday of likely terrorist attacks, possibly by Al-Qaeda, in or around New Delhi and Mumbai in the run-up to the country's Independence Day celebrations next week.

The warning came a day after British police said they had arrested 24 people and foiled a major plot to attack trans-Atlantic airliners.

"We have urged US citizens to keep a low profile, be alert and attentive to their surroundings," an embassy spokesman said.  "The embassy has learnt that foreign terrorists, possibly including members of Al-Qaeda, allegedly intend to carry out a series of attacks," he said, adding the attacks might occur in or around New Delhi and Mumbai.

The information was gathered by US intelligence agencies and the embassy was working closely with the Indian Government, he added. 

"Likely targets include major airports, key central Indian Government offices, and major gathering places such as hotels and markets," he added. 

Mumbai was hit by a series of bomb blasts exactly a month ago which killed 186 people and wounded hundreds more.