Police in Jakarta have uncovered the chassis number of the van thought to have been used in last Thursday's bomb attack outside the Australian embassy.
CCTV images show people running in panic amid the smoke and dust
Similar information proved vital in the hunt for those behind the Bali bombings in October 2002.
Police have also found traces of chemicals used the bomb at a house near Jakarta.
At least nine people were killed in Thursday's explosion, and more than 180 were wounded.
"The chassis number of the vehicle used in the bombing has been discovered," Australian
Federal Police Commissioner Mick Keelty said on Monday.
"People might recall that that was one of the early leads
in the Bali bombing that led to the identification of those
responsible," Mr Keelty said.
There is mounting speculation that the militant network behind the Bali attack - Jemaah Islamiah - also carried out the Australian embassy bombing.
Investigations into the blast continued on Monday, with Australian forensic experts helping Indonesian police in their search for clues.
Indonesian police chief General Da'i Bachtiar confirmed that investigators had discovered traces of TNT and sulphur nitrate - chemicals used in the embassy bomb - at a house near Jakarta.
Police say they believe the bomb, made from around 200kg of explosives, was packed into the back of a white minivan and detonated as close as possible to the target.
Indonesian police say they have also
found suicide notes from men suspected of taking part in the attack.
Police said this vehicle carried the bomb
"We have found letters for their parents which said that they
were going to carry it (the suicide bombing) out," Mr Bachtiar told reporters.
Investigators are trying to determine whether the remains of two unidentified bodies at the scene of the explosion are those of the suicide bombers.
DNA samples taken from the remains have been sent to Australia for further analysis.
The authorities in Malaysia are also helping in the hunt for the perpetrators of the bomb attack.
Indonesian police have named a fugitive Malaysian bomb-making expert, Dr Azahari Husin, as a suspect, along with another Malaysian JI member, Noordin Mohamad Top.
Malaysian Defence Minister Najib Razak told Reuters new agency that he would not be surprised if Islamic radicals already on Malaysia's most-wanted list were involved in Thursday's attack.
Officials based in western embassies are continuing to warn of the possibility of another attack.
People are being advised to avoid large apartment complexes, particular those in the same district as the Australian mission.
Australian Prime Minister John Howard said over the weekend that he would increase security at Australia's diplomatic missions around the world in the wake of Thursday's attack.
The Australian embassy in Jakarta and its consulate in Bali will be relocated, and bomb-proof windows will be installed in other Australian embassies, Mr Howard said.
Mr Howard faces criticism in Australia, after both he and Foreign Minister Alexander Downer said last week that an SMS message warning of the attack had been sent to Indonesian police 45 minutes prior to the blast.
The Indonesian police rejected the claim, and Australian officials now concede that the SMS warning may never have existed.