The man arrested over an attack on federal MP Helen Haines allegedly made a U-turn in a four-wheel drive before striking her, reversing and then hitting her a second time.

Haines, 65, was outside her electorate office in Wangaratta, in Victoria’s north, when she was struck by the vehicle and sustained critical injuries, at about 3.35pm on Monday afternoon.

The independent member for Indi was airlifted to a hospital in Melbourne, where she underwent surgery overnight, but remains in critical condition.

“What witnesses have described is the driver doing a U-turn to get into the car park and to ram Helen against a vehicle, then to reverse and do it a second time,” Home Affairs Minister Tony Burke told ABC Radio on Tuesday.

“A bystander ran towards the scene, got the driver out of the vehicle and held the driver until police arrived.”

Prime Minister Anthony Albanese told News24 that Dr Haines was retrieving something from the boot of her car when she was hit, with eyewitnesses describing her being pinned between the two vehicles when a bystander intervened.

A 43-year-old man from the nearby town of Tarrawingee was arrested in connection with the alleged attack, which is also being investigated by counter-terrorism authorities.

Victoria Police Acting Superintendent Ashley Mason said on Tuesday there was no evidence the man was previously known to law enforcement.

“There’s certainly no recent intelligence that I’m aware of that put him on our radar,” he told ABC News.

The man will be questioned by investigators later on Tuesday morning after he was held at Wangaratta police station overnight.

Major crimes officers had travelled from Melbourne to the northern Victorian town to examine the crime scene, Mason said, adding the investigation would zero in on potential political motivation for the attack.

The incident is being investigated by Victoria Police’s counterterrorism taskforce in conjunction with spy agency ASIO and the Australian Federal Police, with the prime minister saying he will be briefed later on Tuesday.

Authorities are yet to determine the suspect’s motive or establish whether he is known to Haines.

Dr Helen Haines, pictured with husband Phil. Photo: Instagram

The attack has been labelled clearly deliberate by Albanese.

“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,” he said.

A knife was seized from inside the vehicle after the bystander performed a citizens’ arrest.

“I think every Australian is grateful for those moments when a hero like this runs towards the most dangerous place,” Burke said.

Mason personally thanked the civilian for coming to Haines’ aid.

“This would have been such a dynamic, horrific incident to be exposed to,” he said on Tuesday.

“For that individual, for any other person who came to the aid of the injured female, or assisted in the detention of that male prior to police arrival, I’d just like to personally thank you.”

Threats of violence ‘through the roof’

On Tuesday morning, Parliament House was awash with reflections on Haines and her work, including her gentleness toward security guards and ordering of dozens of piccolo coffees from the internal cafe for her staff.

Following the apparent attack, several high-profile female politicians have also warned that threats of serious violence are becoming increasingly common.

“The threats of violence have gone through the roof in the time I’ve been there,” said Social Services Minister Tanya Plibersek, who entered parliament in 1998.

“Rape and death threats are regular.”

In the last year, reports of harassment towards Australian politicians rose from 951 to 1067.

Attacks on electorate offices have also grown.

Plibersek and her colleagues, including independent MPs Sophie Scamps and Monique Ryan, spoke with emotion as they recounted the popularity of the regional Victorian MP.

All of them stressed the importance of politicians staying accessible to the public, even as poor treatment towards them rose.

“This is the worst possible thing to happen to the best possible person in the world,” Ryan told ABC Radio.

“Helen is extraordinary and I wouldn’t say that if I didn’t mean it.”

Scamps, who called Dr Haines a “strong advocate for democracy”, said it was an attack on the core of Australian politics.

“There’s times during pre-election or the election campaigns where I think hatred and division is stoked purposefully, and I’ve had people being incredibly aggressive to me,” the northern Sydney MP said.

“I really hope that we don’t, you know, feel unsafe in our communities.”

Helen Haines with fellow rural independents Bob Katter, Rebekha Sharkie and Andrew Gee. Photo: Mike Bowers

Haines was praised by the Centre for Public Integrity, with which she has worked closely.

“She is passionate, principled, intelligent, warm and down to earth,” the centre said in a statement.

“We are shocked by the increasingly hostile environment in which Australian parliamentarians are working.

“Our democracy depends on people being willing and able to serve their communities, engage openly with the public and advocate for what they believe in, without fear for their personal safety.”

The sentiment was echoed by Climate200, the Simon Holmes a Court-led organisation that backed Dr Haines and other independents in the last two elections.

“There is no place for violence in politics,” the organisation said.

–AAP