Election banners belonging to Attorney-General Christian Porter have been slashed with box cutters in an act he says “flies in the face of our democracy”.

Mr Porter, who is battling to retain his seat of Pearce, said a number of election banners in the Swan Valley and Northam had been targeted over the long weekend.

The vandalism comes just days after a suspected arson attack in Oakford on an election bus supporting fellow WA Liberal Andrew Hastie’s campaign.

“This is a cowardly act – instead of being part of the discussions about what’s important in a competitive healthy democracy, opponents of the Liberal campaign resort to damaging property in the dead of night,” Mr Porter said.

Camera Icon Vince Borrello and Liberal Andrew Hastie at the site of the bus fire. Credit: Mogens Johansen

“My banners are paid for with small donations from people across my electorate who believe in what the Liberal Government is doing.”

Mr Porter said the attacks happened while both major parties had halted campaigning and advertising.

“These criminals spent their Easter long weekend driving around looking for property to destroy,” he said.

Camera Icon Christian Porter called said the vandalism ‘flies in the face of democracy’. Credit: Steve Ferrier

“The people whose homes and business are displaying my signs are exercising their democratic right but when thugs turn to vandalism and criminal acts to assert their views they are essentially taking that right away from them.

“Unfortunately we are seeing more and more of this type of behaviour. It absolutely flies in the face of democracy and it has got to stop.

“People shouldn’t be fearful of their property being damaged because they hold an opposing view to someone else.”

Overnight on Thursday, it was Mr Hastie whose campaign was targeted.

He said his bus was parked at the corner of Thomas and Kargotich roads in Oakford when someone doused the ground nearby with an accelerant and set alight in a bid to blow up the bus.

The former SAS officer said no damage was done to the bus thanks to moisture levels in the soil and the quick actions of firefighters.

But he decried what he said was the cowardice of those who carried out the attack, saying they were “cretins” who had no regard for public safety.

“These people are too cowardly to step into the public square and have a political fight so they’ll use Taliban tactics to try to burn down your bus,” he said.