Victoria Police said a white Toyota Landcruiser struck the 65-year-old just before 4pm. A 43-year-old man from Tarrawingee was arrested at the scene by a passerby after exiting the vehicle, and police located and seized a knife from inside the car. Officers are investigating whether the act was intentional and said it is not yet known whether the two parties knew each other.
Albanese said Haines was allegedly "attacked", described her as "a thoroughly decent human being, full of integrity and respected right across the parliament", and thanked first responders for their "extraordinary work". He said he had been briefed by Australian Federal Police commissioner Krissy Barrett. Home Affairs Minister Tony Burke said the investigation was in the "very early stages" and noted that reported harassing and threatening behaviour against people in high office had risen from 951 to 1,067 incidents in the most recent financial year. Albanese later told the ABC that the temperature of political discourse in Australia and abroad had "undoubtedly been increased", urging Australians to debate their differences respectfully rather than with "personal rancour".
Haines, a mother of three, has represented the north-east Victorian electorate of Indi since 2019.
Opposition Leader Angus Taylor said he was "deeply saddened and distressed" by the news, describing the incident as a "shocking day for our nation" and saying "no one should be targeted in this way". He said he and Albanese were "united in our view that political violence must never be accepted as part of public life". Greens leader David Shoebridge said he was "horrified to hear" of the alleged attack, calling Haines "an extraordinary human being" who "brings people together like few others". One Nation leader Pauline Hanson said violence against any elected representative "is never acceptable in Australia".
Haines' family confirmed she was receiving medical care and thanked bystanders, health workers and police for their response. They asked for privacy and said neither the family nor Haines' staff would be making further comment.