Authorities said initial investigation revealed similarities between Thursday's attack and the August 2003 car bombing of the American-owned JW Marriott hotel in central Jakarta, as well as the October 2002 blasts in a Bali nightclub that claimed over 200 lives.
The latest bombing, which occurred at 10:30 am, tore a five-metre-wide hole in the gate outside the heavily fortified Australian mission, located on a busy downtown thoroughfare.
It obliterated a police checkpoint outside the embassy, killing at least three Indonesian officers, and destroyed several city buses.
The force of the blast blew out the windows of neighbouring high-rise buildings, sending thousands of office workers streaming into streets littered with glass and paper.
The mangled remains of a blackened police truck remained in front of the embassy where several large military style-tents have been erected to assist the forensic investigation.
The torso of a body was discovered in a construction zone 200 metres from the embassy.
Many of the injured taken to the nearby Metropolitan Medical Centre were treated for injuries caused by the flying glass. A steady stream of ambulances transported the most critically injured to larger facilities.
"There was a very big explosion which knocked me down in front of my desk," said secretary Lasmi, holding a cloth to a wound on her forehead.
"The ceiling started to fall in and there was glass everywhere. When I looked outside there were no windows, and I could hear car horns. There was a big plume of smoke above the embassy."
There are differing accounts of what exactly happened. Speaking at the scene, national police chief Dai Baktiar said a car bomb was used in the attack.
Evacuating one of the men hurt
in the Thursday morning blast
However, a Western intelligence source close to the investigation believes there was also a motorcycle involved. Witnesses report hearing a rolling series of at least two explosions which were felt up to four kilometres away.
Citing increased security threats both the US and Australian embassies in the past week issued new advisories urging their citizens to defer travel to Indonesia.
Both embassies are heavily guarded, protected both by armed police officers, cement barricades and blast-proof windows.
"The modus operandi is similar to the past attacks including the Bali blasts and the bombing of the Marriott," Baktiar said.
"I believe … we can conclude they (bombers) are from the same group."
Over the past two years Indonesian police have convicted dozens of members of the al Qaida-affiliated organisation known as Jemaah Islamiyah for their roles in the Bali and Marriott bombings.
The alleged spiritual head of JI, cleric Abu Bakar Bashir is currently in prison accused of sanctioning the hotel blast.
Whereas the majority of the victims of the Bali bomb were foreigners, including 88 Australians, all but one of the Marriott dead were Indonesian nations. It appears all of the dead and injured from the embassy attack are Indonesian.
"The modus operandi is similar to the past attacks including the Bali blasts and the bombing of the Marriott"
Indonesia's National Police chief
In July, reports circulated that JI operatives had slipped into the country from bases in the southern Philippines intent on assassinating foreign businessmen and prominent Indonesian politicians.
Police have confirmed the arrest of six men believed to belong to the "assassination squads" but a source who has seen transcripts of the interrogations says the men are refusing to talk.
One of the key organisers of the Bali bombing has been cooperating with the police investigation.
In an incident that threatened to sour the on-again, off-again Indonesian-Australian ties, convicted bomber Ali Imron was spotted drinking coffee in a popular Starbucks outlet with a senior Indonesian police officer.
Indonesian police have turned
up the heat on armed activists
That officer is responsible for uncovering the locations of other bombs that are believed to have been constructed by JI operatives in Jakarta in recent months.
Indonesian president Megawati Sukarnoputri cut short a visit to Brunei to tour the hospital and embassy. Her opponent in the 20 September run-off presidential election, Susilo Bambang Yudhoyono, visited the site earlier in the day.
As the sun set over the capital, police had begun to explore the interiors of the neighbouring buildings looking for more victims.