A former Victorian Greens MP has revealed he will quit parliament, weeks after stepping down from the party over an affair with a staffer.
Sam Hibbins, the MP for Prahran in inner Melbourne, announced he would resign from parliament as he hit out at what he called a "concerted campaign" against him.
He alleged "unauthorised access" to his office at Victoria's Parliament House.
"Personal items, including family and my children's baby photos, were vandalised with offensive and threatening graffiti," Mr Hibbins posted to social media on Saturday evening.
Mr Hibbins said he had alerted parliamentary services and police but did not provide further details.
"This has become a concerted campaign against me," he said.
"I know many of you will understand that as the father of two young children, I must put the safety and well-being of my family first."
Mr Hibbins is married with two children and has served as the MP for Prahran since 2014, with his resignation setting up a by-election.
"It has been an extremely difficult time for us as the public disclosure of what was a private matter has taken a significant toll on our family's mental health," he said.
Earlier in November, Mr Hibbins revealed he would resign from the Greens and sit as an independent after having a "consensual relationship with a staff member, which breached party rules".
At the time, party leader Ellen Sandell said she had received a complaint about her co-deputy and after meeting with him, said some allegations were confirmed while others were contested.
The staff member involved was "very distressed" and Ms Sandell said the party had been doing all it could to support them.
Mr Hibbins retained Prahran on a 12 per cent margin at the most recent state election, after taking the seat from the Liberals in 2014.
A spokesperson for the Victorian Department of Parliamentary Services told AAP they were aware of the matter raised by Mr Hibbins about his office in Parliament House but could not provide any further information.
