Paul Harbon, who was eating breakfast downstairs at the time, had an easier time evacuating than his wife, who was in the couple's room.

'I ended up in the bottom of the building,' she said. 'There was floodwater everywhere, and there were no lights. I just screamed and screamed until someone came to get me out.'

The hotels, connected by an underground tunnel and located in a business and diplomatic district, were popular with foreigners as a venue for business meetings because they were thought to be well-protected. The Harbons said they had been impressed with the security when they checked in Thursday night.

The blast was the second bombing on the Jakarta Marriott. In August 2003, a militant drove a bomb-laden truck into the lobby of the hotel and set it off, killing 12 people and injuring 150.

'The only group that has the ability to carry out such attacks is Jemaah Islamiyah,' terrorism expert Rohan Gunaratna told Channel News Asia.

Until Friday, Indonesia had not had a major bombing since October 2005 when militants belonging to Jemaah Islamiyah blew themselves up at three restaurants in Bali, killing 20 people.

Jamaah Islamiyah, also known as JI, is also blamed for the October 2002 Bali bombings, which killed 202 people, mostly foreign holidaymakers.

Analysts have said that the group's violent faction has been severely weakened after the arrests of scores of operatives in recent years but determined militants were still capable of mounting a deadly attack.

'The signs were there over the last few months that this hard-line group within JI was disaffected with the lack of a bombing campaign over the last couple of years and was clearly intent on doing something,' said defence analyst Carl Ungerer, director of the Canberra-based Australian Strategic Policy Institute.

The hotel bombings came a little more than a week after the July 9 presidential election, in which Yudhoyono appeared set to win a second five-year term although the final results have yet to be officially confirmed.

Yudhoyono has been credited with restoring security after a spate of deadly attacks blamed on Jemaah Islamiyah since the start of the decade.

English Premier League champions Manchester United cancelled their plans for friendly match with an Indonesian All Star, scheduled for Monday. The Manchester United players were due to stay at the Ritz-Carlton.