The suicide bombers behind the deadly twin blasts at Jakarta hotels on Friday were members of the al-Qaeda-linked regional terror outfit Jemaah Islamiyah, Indonesian police said today.

Police also confirmed they had identified one of the two suicide bombers.

Jemaah Islamiyah (JI) has carried out dozens of bombings in Indonesia over the past decade including the 2002 attacks in Bali that left more than 200 dead, mostly foreign tourists.

"We confirm that the attackers are from Jemaah Islamiyah because there are similarities in the bombs used," Indonesia’s national police spokesman Nanan Soekarna told a press conference in Jakarta earlier today.

He said an exploded bomb left in a guestroom of the JW Marriott, which was attacked along with the nearby Ritz-Carlton, resembled devices used in the Bali bombings and one discovered in a recent anti-JI raid on an Islamic boarding school.

"They are from the same school. We found similar tools, similar materials and similar methods," he said.

Police have identified one of the two suicide bombers who targeted the hotels during the breakfast period on Friday when they were packed with foreign businessmen and diplomats.

"Following the preliminary results of facial reconstruction, both suicide bombers are male," Mr Soekarna said, quelling speculation that a woman was involved.

"One of them has been identified. I cannot tell you his complete name but he has the initial 'N'. And another body is still in the process of identification."

Nine people were killed in the attacks, including three Australians and a New Zealander who have been confirmed dead. The health ministry said a Singaporean man was also killed but did not give a complete name and the Singapore embassy here said it had not verified the death.

An Indonesian man identified by the single name Darmanto was also among those killed.

Soekarna has said 16 foreigners were injured, including six Americans, two Dutch, one Australian, two Canadians, one Indian, two South Koreans, one New Zealander and a Norwegian.

Earlier today the Australian Foreign Minister Stephen Smith visited the site of the attacks, as part of a trip to express solidarity with Australia's northern neighbour.

Investigators say the bombers stayed in Room 1808 of the Marriott for two nights before the attacks and disguised themselves as guests when they walked into crowded dining and meeting areas and detonated their suitcase devices.

The bombs - brought into the hotels despite airport-style security measures - were packed with metal nuts to maximise the carnage.

The Indonesian security ministry's anti-terror desk chief, Ansyaad Mbai, has said that evidence pointed to Malaysian-born extremist Noordin Mohammed Top, who leads a violent splinter faction of JI.

Noordin is accused of masterminding bombings at the Jakarta Marriott in 2003, the Australian embassy in 2004 and Bali restaurants in 2005 which have killed more than 40 people.

Mr Mbai said the advanced skills and planning used to pull off the blasts at the luxury hotels - among the most tightly guarded buildings in Indonesia - were extremely disturbing.

"Their new skills and advanced tactics, enabling them to smuggle the explosives into the targeted site, pose a very serious threat for our country," he told AFP.

"While they previously detonated the bombs from outside of the targeted place, now they managed to smuggle the bombs into the hotel and stayed several days in the hotel room where they planned the attacks," he said.

"Nobody can predict terror attacks. What we can do is to review our security system to get a more effective approach."

National police chief General Bambang Hendarso Danuri has called on hotels and shopping malls across the vast, mainly Muslim archipelago of 234 million people to raise their security protocols in response to the bombings.

The attacks triggered the cancellation of a planned Manchester United friendly against an Indonesian All-Star team scheduled for Monday, a decision that caused great dismay among football fans in Jakarta.

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