It was a busy night for emergency services in the Latrobe Valley following a house fire at Morwell and an assault at Newborough.
Police were called to a Central Avenue, Newborough unit about 9.30pm on Monday following reports of an argument between two males.
Neighbours reported hearing loud noises at the property before police arrived and located a man outside the property with his face covered in blood.
A second man was found on a bed inside the unit with serious facial injuries, police said.
The first man - a 44-year-old from Newborough - was arrested and taken to Latrobe Regional Hospital for treatment under police guard.
The second man - a 41-year-old Newborough man - was airlifted to The Alfred hospital where he remains in a serious but stable condition.
Both men are yet to be interviewed by police.
In a separate incident, police are investigating a fire on Church Street, Morwell after a dispute between the resident of the property and an acquaintance of the resident.
Police said a minor assault occurred before the resident and the offender left the property separately.
The resident returned a short time later and saw smoke billowing from the home before noticing two gas bottles alight inside his house.
Police said the gas bottles were thrown through the front window of the property, according to the victim.
The CFA were called and extinguished the blaze about 5am which has extensively damaged the interior of the house.
An arson chemist is expected to visit the scene later today.
No charges have been laid in either incident.