Two activists accused of forcing the evacuation of Woodside’s Perth headquarters with stench gas are facing tougher charges as police claim more employees suffered ill effects.

Disrupt Burrup Hub campaigners Kristen Morrissey and Joana Partyka faced Perth Magistrates Court on Thursday after prosecutors filed fresh charges against them.

They’re now facing six counts each of acts or omissions causing bodily harm or danger to any person and one count each of act with intent of creating false belief of threat or danger.

The pair allegedly released a non-toxic stench gas called ethyl mercaptan in the lobby area of the oil and gas company’s building on June 1, forcing more than 2000 employees to leave the building.

A police bomb response unit and firefighters were called amid chaotic scenes, with workers unable to return to their desks until later in the day.

It was a protest against Woodside’s plans to expand its gas operations on the rock-art-rich Burrup Peninsula in Western Australia.

But police alleged some employees experienced health issues as a result of the incident.

Ms Morrissey was initially charged with four counts of causing bodily harm or danger.

Ms Partyka, who admitted criminally damaging Frederick McCubbin’s work Down On His Luck at the Art Gallery of WA during another protest against Woodside, hadn’t previously been charged over the June incident.

They were represented by lawyer Nick Terry after their usual defence counsel was unable to return to Australia to appear in court.

“I appear today for Zarah Burgess who is detained overseas, ironically, by climate change – her flights cancelled by record heatwave and hurricanes,” he said.

The matters were adjourned for mention to September 28 and Ms Morrissey’s onerous bail conditions that forced her to remain at home unless she was going to work were lifted.

In a statement issued on Thursday, Ms Partyka denied involvement in the protest.

“I wasn’t even involved in this action – I have been roped in on the flimsiest of pretexts, involving a roll of sticky tape and an alleged recording with passing reference to a plan,” she said.

“I was nowhere near it on the day.”

Ms Morrissey, however, did say she took part.

“It went flawlessly to plan. We evacuated the building entirely, all day, and prevented them from f—ing up the Burrup for one extra day,” she said.

“Genuine disruption is the most effective way to stop Woodside’s Burrup Hub, and we’re winning.”

The Burrup Peninsula, located in WA’s Pilbara region and known as Murujuga to traditional owners, contains the world’s largest and oldest collection of petroglyphs.