Jakarta hotel attacks believed to be the work of suicide bombers; 8 killed

JAKARTA, Indonesia (CNN) - Indonesian police believe two suicide bombers checked into the JW Marriott Hotel in Jakarta and carried out attacks on Friday morning that killed at least eight people and wounded more than 50 others, the national police chief said.

It is unclear what group is behind the attack on the Marriott and the adjacent Ritz-Carlton. National Police Chief Gen. Bambang Hendarso said the death toll could rise.

Indonesian authorities have detained several witnesses and others for questioning, and have sent forensic evidence from the seen for testing, a spokesman for Indonesian President Susilo Bambang Yudhoyono said.

"It's all being studied now," Dino Patti Djalal told CNN.

Yudhoyono also cast doubt on who was behind the attack.

"This terrorist action is thought to be the work of a terrorist group, even though it is not certain whether this is the terrorism which we are familiar with up until now," the recently reelected president said.