Labor MP Peter Khalil's electorate office has been vandalised with red paint and doused with an unknown substance in what he has called an "escalation" of previous incidents.
Photos provided to the ABC by Mr Khalil's office show the signs and exterior of the building in Melbourne sprayed with red paint, with "land back" and "glory to the martyrs" written along the walls.
Mr Khalil, who is the government's first special envoy for social cohesion, said that a hole was drilled in a door and "fire extinguishers and other kinds of propellants" were used to push "substances into the office".
A hazmat team was called to determine whether the substance was dangerous, and staff were evacuated.
"We're just not sure what's in there, the smell is horrific," Mr Khalil said on Monday.
"It smells like an abattoir and it's hard to breathe nearby it."
An inverted red triangle was painted on a door to the office, which is a symbol that is associated with Hamas. (Supplied: Office of Peter Khalil)
The photos also show an inverted triangle painted on a door, a symbol associated with Hamas, a terrorist organisation.
Victoria Police confirmed it was investigating criminal damage at an office in Brunswick and that it was understood the damage took place between 2am and 9am on Monday.
Officers were told that offenders had poured an unknown liquid through the door, the police spokesperson said.
Politicians' electorate offices have repeatedly been the target of protests and vandalism in the wake of the war in Gaza.
Labor MP Josh Burns's St Kilda office was damaged in June when vandals smashed the windows and painted the exterior with slogans.
Following that incident, Prime Minister Anthony Albanese called for the protests and vandalism to be dialled down.
"For some people, they feel very strongly about issues in the Middle East. But it's no reason to target MPs half a world away in Australia, and in particular the targeting of a Jewish MP is very distressing," he said at the time.
Peter Khalil's electorate office in Melbourne on Monday. (Supplied: Peter Khalil's office)
Late last year, Mr Khalil was also among a handful of Labor MPs who had fake dead bodies dumped outside their offices alongside signs with pro-Palestinian messages.
"You can say that we've experienced this pretty consistently over a period of time, but it still doesn't change the fact that everyone deserves to be safe at work," Mr Khalil said.
"The instance that we've seen today that puts other people in danger, that puts my staff in danger, that is both unacceptable under the law and also unacceptable morally."
Mr Khalil, who is the son of Egyptian migrants, has represented the seat of Wills in Melbourne's inner north since 2016.
He was appointed as the special envoy for social cohesion in July, tasked with working across communities to promote harmony.
"This is one of the major challenges to our cohesion, that people think it's OK to take these kinds of actions to express themselves," Mr Khalil said.