Independent member for Indi Helen Haines has lost a leg and remains in a critical condition after being hit by a Toyota LandCruiser outside her electorate office in Wangaratta, northern Victoria, on Monday afternoon.
Brendan Nugent, a 43-year-old man from nearby town of Tarrawingee, has been identified as the driver and is in custody. No charges have been laid.
In a statement, his father Rod Nugent and Rod's partner Christine Cunningham said Dr Haines had been their friend for more than 20 years.
"What happened to her yesterday is devastating and unfathomable," they said.
"We would like to sincerely thank members of the local community and police who came to Helen's aid yesterday after the shocking and horrific crime. We will be assisting Victoria Police in any way we can.
"Helen Haines is a deeply respected, valued and much loved member of our local community."
The 65-year-old was at the boot of her car when the four-wheel drive allegedly made a U-turn, hit her, reversed and hit her again, according to witness accounts relayed by government ministers.
Counter-terrorism authorities are investigating the incident.
The MP was airlifted to Melbourne's Alfred Hospital and remains in a critical condition after undergoing surgery overnight, with sources confirming to AAP she had lost one of her legs.
Dr Haines' husband Phil, daughter Georgia and sons Nick and Will were seen briefly emerging from the hospital on Tuesday afternoon, where they have been at her bedside.
Nugent had reportedly been apprehended behind the wheel of the LandCruiser by local barber Ricky Jefferies, who says the driver had a knife, before police arrived to detain him.
He was held at Wangaratta police station overnight and questioned on Tuesday morning and is yet to be formally charged.
Authorities have reportedly blocked access to an address connected to Nugent not far from Wangaratta.
Back in town, locals crowded a church for a vigil in support of Dr Haines.
State Nationals MP Tim McCurdy told AAP he had come across Nugent before, but said his interactions with him were non-aggressive.
"He wasn't threatening to any of our staff," he said.
In the neighbouring federal electorate of Nicholls, Nationals MP Sam Birrell said he had tried to stick to business as usual.
"I still went to the two country towns to speak to the grade 6's at the primary school. I walked down the street to catch up with some businesses," he told AAP.
"(I) was probably more aware of my surroundings, a little bit more than I had been."
It is not clear whether the alleged attack was politically motivated, as Victoria's counter-terrorism task force is joined by federal police and spy agency ASIO in the investigation.
There was no recent evidence Nugent was on authorities' radar before the alleged attack, Victoria Police Acting Superintendent Ashley Mason said on Tuesday.
It appeared to be a standalone incident with no enduring danger, AFP Commissioner Krissy Barrett said.
Federal and Victorian police have briefed Prime Minister Anthony Albanese and Home Affairs Minister Tony Burke, along with Victorian Premier Ben Carroll.
Mr Albanese has alleged the attack on Dr Haines was clearly deliberate.
"This wasn't something with a car just going off the off the road; this is something that is very clear was aimed at causing harm to Helen Haines," the prime minister told News24 on Tuesday.
The AFP is gearing up to deliver more security briefings to federal MPs after reporting a rise in threats against federal parliamentarians, high office-holders and electorate officers in recent years.
A task force to disrupt high-impact, politically motivated violence and similar potential crimes has already charged 41 people for threatening politicians and higher-ups since being established in October 2025, according to the agency.