Brisbane man allegedly fatally stabbed his ex-wife’s new partner in front of children

A father is in under police guard in hospital after allegedly fatally stabbing to his ex-wife's new partner in front of three children in  a home in Brisbane's east.

Police were called to reports of children covered in blood walking outside the home on Brompton Street in the bayside suburb of Alexandra Hills about 11.50pm last night.

Investigators allege a 39-year-old man smashed his way into his ex-wife’s home before stabbing her new boyfriend. Authorities said the 39-year-old also suffered critical injuries.

He was taken to hospital and remains there in a critical condition.

The dead man has been identified as 37-year-old Darly Corcoran. He was found dead inside a bedroom in the home.

"The first responding police turned up to a horrific scene," Queensland Police Inspector Rob Graham said.

"You can just imagine what the kids and the ex-partner have been through."

A crime scene has been established and a forensic team is now investigating.