Arrested man was anti-logging campaigner, environment group tells ABC:

Brendan Nugent, who has been arrested by police over the attack on Helen Haines, was an anti-logging campaigner who had previously been involved with the Save our Strathbogie Forest group:

Chairperson Bertram Lobert told the ABC Nugent was an active member for about two years before the COVID-19 pandemic hit, but he hadn't heard from him since then.

He said Nugent would drive an hour from his Tarrawingee home to get to the group's meetings.

"At the time he was an intensely intelligent man interested in the issues our group was interested in," Lobert said.

"He was a person who cared about the environment. He got on generally well with people."

He said he was in shock to learn Mr Nugent had been arrested over the attack on Ms Haines.

"The whole thing is so sad … we have members of our group who are friends with Helen," he said.

"So it's real, it's immediate. It's going to hurt."