Angus Hohenboken – Two Indonesian suicide bombers were filmed discussing martyrdom and being instructed to target Australians, just weeks before they blew up two Jakarta hotels, killing seven people, including three Australians.

The video was found on a laptop in a backpack worn by terrorist leader Noordin Mohammed Top after he was killed by police during a raid on a home in central Java earlier this month.

Lounging back in a park across the road from the Ritz-Carlton, terrorists Dani Dwi Permana, 18, and Nana Ikhwan Maulana, 28, chat in the footage with an unseen cameraman, who tells them "this is our target".

"America has to be destroyed," the cameraman says. "Australia has to be destroyed. Indonesia has to be destroyed."

Permana, a high school graduate, justifies the violent act through an extreme interpretation of his religion. "This is a very noble way to destroy the enemies of Islam," he says. "This is not suicide. Suicide is only for frustrated people."

Three weeks later, the men walked into the lounges of the Ritz-Carlton and Marriott and triggered bombs that killed seven people, including Australians Craig Senger, Garth McEvoy and Nathan Verity, and wounded more than 50 others.

The cameraman, believed to be fugitive Top follower Saifuddin Jaelani, is alleged to have recruited the bombers.

Releasing the footage yesterday, Indonesian police aired suggestions that the terrorist group planned to increase the frequency of their attacks to as often as once a month, citing evidence found in a separate raid on a terror safehouse in Jati Asih, outside Jakarta.

Attacks had previously been carried out annually with the Bali bombing in 2002 and first bombing of the Marriott in 2003, followed by the Australian embassy in Jakarta attack in 2004 and a second Bali in 2005.

Detective Tito Karnavian, of the Indonesian police anti-terror unit, said the group had planned "serial attacks", with another bombing, this time targeting Indonesian President Susilo Bambang Yudhoyono, scheduled for August in Jati Asih.

A letter on the laptop seized by police and allegedly written by Jaelani to his family in July detailed the level of organisation within Top's group, with responsibilities divided between religious guides, financial managers, recruiters and others charged with sourcing weapons and cars or protecting the families of "mujahid" or holy warriors.

Mr Karnavian said police still regarded the network Top built as a potent threat despite his death. The laptop contained evidence the group had re-established links with Middle East terrorist groups such as al-Qa'ida.

Other videos on the computer show the bombers stretching and jogging on a road that passes the hotels, scoping out their target. (Additional reporting: agencies)