The family of a young Queensland constable gunned down in a terror attack that shocked Australia has released a harrowing statement on the anniversary of his death.

Constables Matthew Arnold, 26, and Rachel McCrow, 29, were shot in cold blood by deranged killers Nathaniel, Gareth and Stacey Train after jumping a fence at a property at Wieambilla, west of Brisbane, for a routine welfare check.

Neighbour Alan Dare was also shot dead before the Trains were killed in a gunfight with specialist police on the night of December 12, 2022.

Constables Randall Kirk and Keely Brough survived the attack.

A year on from the heinous triple killings, with emotions still raw, Queensland Police marked the milestone with a minute’s radio silence at 4.36pm on Tuesday (AEST) – the exact time the young officers entered the Trains’ property.

On Tuesday, Arnold’s family released a statement through Queensland Police saying December 12 marked a day of “incomprehensible evil”.

“We miss Matt’s laugh, kindness, empathy and willingness to help,” they said.

“These traits were what made him such an excellent police officer and made him love his job.”

The family also paid tribute to McCrow’s bravery and courage.

“We will forever stand with the McCrow family in the pain they feel with losing Rachel,” they said.

“We also remember Alan Dare on this day.

“We wish we could count down the days until we see Matty again, instead we will live our lives as he would want, making him proud and ensuring no one forgets him and his sacrifice.

“The tears still flow freely and will forever sting, but we can’t wait to share stories with him over a drink, and some country music again one day.”

Queensland Police Union President Ian Leavers said McCrow’s sister recently gave birth to a boy – a nephew she will never meet, while Arnold was a triplet and his family was still grappling with his death.

“That gut-wrenching pain, which all of us felt on that day, will never, ever be forgotten,” Leavers said.

“The way that they were callously executed in cold blood has resonated with every police officer in Queensland because they know it didn’t have to occur, it should never have occurred. But it could have been any one of them, just responding to a call for service.”

Stacey and Gareth Train’s adult children, Madelyn and Aidan, also released a statement through Queensland Police on Tuesday.

“We acknowledge Nathaniel and Gareth Train were involved in the murder of Matthew Arnold, Rachel McCrow and Alan Dare,” they said.

“All who are hurt by the loss of Rachel, Matthew and Alan have our condolences and sympathy; know that we grieve their deaths with you.”

Aidan Train said he and his sister had also lost the family that raised them.

“This was the only family we had in our childhoods, due to estrangement from our extended family. Stacey, Gareth and Nathaniel were all shot fatally while armed,” he said.

The siblings said they did not share their parents’ extreme religious beliefs, or their views of the police.

“We have given the police and coroner our full cooperation to ensure the investigation into the tragic incident can be completed quickly,” they said.

“We are truly sorry for the suffering our parents have caused and the impact their actions continue to have.”

A year on from the killings, the police union is adamant it will one day acquire the Wieambilla property so it can never again “be used for evil”.

As well as the minute’s silence, some Queensland police stations planned to host morning teas on Tuesday to remember their fallen colleagues.

“Matthew and Rachel’s family … are in pain each and every day, and they do not want to publicly come out on the anniversary,” Leavers said.

“But they’ve asked me to convey the message, please never forget Matthew, never forget Rachel, don’t forget their families, but make sure that [we do] anything that we can do [to] prevent a tragedy like this happening into the future.

“Don’t let their deaths go in vain.”

Following years of concerns about gun-related crime around Australia, a meeting of federal, state and territory leaders last week agreed to establish a National Firearms Register within four years.

The agreement was reached on the day a radical American preacher was arrested by the FBI in connection with the Queensland attack.

Conspiracy theorist Daniel Day is accused of sending “Christian end-of-days ideology” to the Trains in the lead-up to the killings after they connected on YouTube.

After they killed the officers and Dare, the Trains filmed a YouTube video during which they told “Don” they loved him and they would “be home soon”.

– with AAP