President Susilo Bambang Yudhoyono of Indonesia has condemned the hotel bombings in Jakarta as "cruel and inhuman."
At least nine people were killed, including a New Zealander, Timothy Mackay. At least 50 people were wounded, including many foreigners.
The dead include two suspected suicide bombers.
One explosion was at the Ritz-Carlton hotel and the other was at the JW Marriott.
After visiting the scene on Friday, he said the bombings were the act of a terrorist group bent on damaging the country.
However, the president said it was too early to say whether Jemaah Islamiah was involved.
No group has yet claimed responsibility for the blasts.
The Jakarta Marriott hotel was previously bombed on 5 August, 2003. Eleven people were killed.
The Australian Embassy in Jakarta was bombed on 8 September, 2004: 11 Indonesians were killed and 180 wounded.
JI organised the Bali bombings on 12 October, 2002, in which 202 people were killed including 88 Australians and three New Zealanders.
Three "Bali bombers' were executed by firing squad in November 2008.
In the second Bali bombings: 23 were killed including four Australians and three suicide bombers in restaurants on 1 October, 2005.
Bombers were guests - police
Police said the bombers checked into the Marriott as paying guests on Wednesday and assembled the bombs in their room, number 1808.
A third bomb was found and defused in a laptop computer bag on the 18th floor.
TVOne in Indonesia showed closed-circuit television footage of a suspect at the Ritz-Carlton. He was wearing a baseball cap and pulling a wheelie-bag through the lobby.
Police say the casualties include citizens of Indonesia, the United States, Australia, South Korea, the Netherlands, Italy, Britain, Canada, Norway, Japan and India.
New Zealand Prime Minister John Key has expressed his sorrow at the death of Mr Mackay and extended his sympathy to Mr Mackay's family.
Mr Mackay worked for the Indonesian arm of the Holcim cement company. He moved to Indonesia in 2004 from Fiji.
Mr Key said the bombs may have a specific signature, which could reveal who made them.
The Ministry of Foreign Affairs says it has confirmed that 50 out of 281 New Zealanders living in Jakarta are safe. Embassy officials are checking hospitals for any other New Zealanders caught in the explosions.
Australian Prime Minister Kevin Rudd said he's "sick to his stomach" at what he describes as barbaric acts of murder.
He said grave concerns are held for the safety of three Australians, one of them an embassy official.
The UN Security Council has issued a joint statement strongly condemning the bombings.
US President Barack Obama, who lived in Jakarta for four years as a child, called the attacks "outrageous".
He said the attacks make it clear that extremists remain committed to murdering innocent people.