Rowan Baxter, the former Australian rugby player, killed self, his estranged wife Hannah Baxter, and the couple’s three children in an apparent murder-suicide Wednesday.

Baxter, who was a member of Auckland's New Zealand Warriors squad in Australia's National Rugby League (NRL), allegedly refilled a gas can at a local service station in Brisbane, CNN reported. He doused the car with the fuel and ignited it while all of them were inside.

Queensland police responded to a car fire at 8:30 a.m. local time (5:30 p.m. EST, Tuesday) in the suburb of Camp Hill. They found the three children, Laianah, 4, Aaliyah, 6, and Trey, 3, dead inside, and Hanna, 31, with burns on the ground beside it. Rowan, 42, allegedly had self-inflicted knife wounds while trying to stop witnesses attempting to intercede. He died at the scene and Hannah succumbed to her extensive burns later at a hospital, BBC reported.

Police told the publication that a history of domestic violence appeared to have triggered the murders and the suicide.

“Devastating news out of Camp Hill. My heart goes out to the families and community going through this tragic time and the emergency responders confronting what would be a shattering scene,” Australian Prime Minister Scott Morrison said in a tweet.

Baxter worked as a fitness coach for NRL, Super Rugby and Australian Football League (AFL) teams after retiring as a player. The couple also ran a gym in Capalaba, Brisbane, over past few years. Hannah moved to her parents’ home with her children last year after separation from her husband.

The incident sparked a nationwide outcry in Australia. There has been an outpour of online tributes.

"#HannahBaxter and her three young children died today in the most despicable way. They should have been safe. Mourning for lives lost, thoughts with family, friends and community," former Olympic cyclist Tracy Gaudry said on Twitter.

The whistle that will kick off the Rugby World Cup
The whistle that will kick off the Rugby World Cup AFP / CHARLY TRIBALLEAU