MP arrested and interviewed as part of police probe

The 45-year-old was arrested at the property, interviewed and released without charge pending further inquiries.

"As the investigation is ongoing and given the sensitive nature of the matter, we will not be commenting further at this time," a statement from Victoria Police said.

Neither the nature of the allegation nor the identity of the alleged victim has been revealed.

Mr Fowles has strenuously denied any allegation of assault.

Former premier Daniel Andrews sought Mr Fowles' resignation from the parliamentary Labor Party in early August after referring the allegations to police.

At that time, police had received the government's referral but were not investigating because the alleged victim had not made a formal complaint.

However, on August 25 the state's police force revealed the Sexual Crimes Squad was investigating a report of an incident in Melbourne's CBD.