The remote bushland property where two police officers were murdered could be used as a retreat or training centre if the Queensland government agrees to clear the way to its purchase.

Constables Matthew Arnold, 26 and Rachel McCrow, 29, died in a hail of gunfire after pulling up to the rural property at Wieambilla, three hours west of Brisbane, on December 12.

Neighbour Alan Dare was also gunned down in the melee sparked when conspiracy theorists Gareth Train, his partner Stacey  Train and brother Nathaniel Train opened fire upon their approach.

The officers were checking the property, owned by Gareth and Stacey Train, while conducting a missing persons check for Nathaniel Train.

The Queensland Police Union said on Tuesday it wanted to buy the block and had asked the government for help resuming the land.

“The QPU would never want to see this land fall into the hands of any other anti-vaxxer, pro-gun conspiracy theorist, sovereign citizens who may seek to utilise the reputation of this site to promote their own dangerous and warped views,” union head Ian Leavers told The Courier-Mail.

“That is why the QPU has an obligation to safeguard this property to protect the memories of the police who gave their lives.”

Mr Leavers told The Courier-Mail the land could be used for a retreat for officers, a training centre and be the site of a memorial.

The government is reportedly considering the proposal.

On Monday, Premier Annastacia Palaszczuk paid her respects to the slain officers ahead of a public memorial at the Brisbane Entertainment Centre on Wednesday.

“Everyone’s gone through a really rough time out here and I want all of Queensland and all of Australia to continue to show their support for the two young lives that were tragically taken,” she said.

“Wednesday is going to be a very difficult day.”

Some 8000 people are expected to attend the memorial before the constables are farewelled by family and friends at private ceremonies.

The public is invited to attend the ceremony alongside family, friends, dignitaries and police officers. Free tickets were available from Monday night.

• See full details for the memorial service at Queensland Police

The service will be live-streamed online and on TV, and Queenslanders will be able to watch the event at public venues across the state, including in communities near Wieambilla such as Tara, Dalby and Chinchilla.

Investigators continue to probe the circumstances of the attack, which fellow officers Constables Keely Brough and her colleague Randall Kirk managed to escape.

After the initial ambush, the Trains were shot dead in a firefight with heavily armed tactical police officers.

Investigators are still to officially declare a motive but are probing links between the Trains and conspiracy groups online and their digital footprints.

– AAP