Warning: The following graphic images may disturb or cause distress. As forensic experts sift through evidence at the bomb sites in Bali, officials release photographs of the severed heads of the suspected suicide bombers.
Indonesian newspapers have published the pictures with appeals for help in identifying the men.
Investigators hope that naming the men will lead them to the identities of those who planned the attack.
Police are also studying amateur video footage which shows a young man with a backpack enter a restaurant moments before an explosion.