Helen Haines’ alleged attacker, Brendan Nugent, has been charged with dangerous driving causing serious injury, intentionally cause serious injury and the commonwealth offence of causing harm to a commonwealth public official.

He will be held overnight to appear at Wangaratta magistrates court on Wednesday, Victoria police confirmed in a statement, adding that it would be alleged the attack was targeted.

Victoria police arrested the 43-year-old Tarrawingee man on Monday afternoon after he allegedly struck the independent MP for Indi with a Toyota LandCruiser outside her electorate office in Wangaratta in northern Victoria.

Haines remains in a critical but stable condition after being airlifted to Melbourne’s Alfred hospital for emergency surgery. She has lost one leg and surgeons were fighting on Tuesday to save the other leg.

Police also said in the statement released late on Tuesday that one of its highway patrol officers responded to the incident only eight seconds after emergency services were called.

They confirmed that a search warrant had been executed that morning at Nugent’s Great Alpine Road property.

“Victoria Police will continue to maintain an enhanced presence in Wangaratta, including members from the Public Order Response Team who have deployed to the area.

“At this stage it appears this is an isolated incident, and there are currently no other known threats connected to this matter.”