The gunmen embarked on their shooting spree after throwing three pipe bombs and one “tennis ball bomb” that failed to detonate, from a footbridge overlooking the mostly Jewish crowd gathered to celebrate the first day of Hanukkah on Dec. 14, New South Wales police said.
“Preliminary analysis indicates the pipe bombs were made of sealed aluminum piping containing explosive, black powder, and steel ball bearings,” police said in the document, describing them as “viable” nonetheless.
The suspects trained in a countryside location — suspected to be in New South Wales — in late October, police said, citing a video found in the younger suspect’s phone that showed them firing shotguns and “moving in a tactical manner.”
The court document included pictures apparently from the video, showing the suspects wearing black t-shirts and pants while firing the shotguns in a green field.

Police said they also found a video recorded in late October, which showed the suspects sitting in front of an image of an ISIS flag as they “make a number of statements regarding their motivation for the ‘Bondi attack’ and condemning the acts of ‘Zionists.'”
From Nov. 1 to Nov. 28, the suspects traveled to the Philippines where they stayed at a lowkey budget hotel, Philippine authorities said last week. The suspects originally booked the GV Hotel for one week and later extended, hotel staff last week told NBC News.
The hotel is located in Davao City on the island of Mindanao, once a hotspot for Al Qaeda and ISIS fighters, which experts say still contains areas where a few dozen ISIS-aligned fighters are believed to be holed up.
On Sunday, Philippines police regional director Brig. Gen. Leon Victor Rosete said the police were conducting “backtracking operations to establish their movements during their stay.”
Police were also probing the “individuals they interacted with and assessing possible links or support networks,” he said in a video statement.
A few days after returning to Sydney, the suspects checked into a room the son had rented through Airbnb from Dec. 2 till Dec. 21, Australian police said in the documents, which do not specify when exactly the duo checked in.
Police also said they recovered several guns and ammunition, a suspected homemade explosive, 3D-printed parts for a shotgun speed loader and two copies of the Quran from the room.

On Dec. 14, the day of the attack, suspects loaded two single barrel shotguns, a rifle, four home-made explosive devices, and two ISIS flags into their car, police said.
Arriving at the site of the massacre, the suspects placed the ISIS flags on the inside of the front and rear windscreen, police said.
“In these locations, both IS flags were clearly visible to the public.”
While the father was killed at the scene, the younger suspect woke from his coma last week and faces 59 charges, including terrorism and 15 counts of murder.