been discharged from the emergency department while two will remain to receive ongoing care for minor injuries.

Both remain in a stable condition.

Mr Cartwright said the student was not known to police or intelligence agencies but no motivation had yet been established.

"At this stage though, ACT Policing have not ruled anything out," he said.

He urged any witnesses who had not yet spoken to police to come forward.

Ms Hughes-Warrington said there would be increased numbers of ANU campus security at upcoming open days in light of the attack.

She described the attack as an "isolated and random incident" and "very unusual".

"[I want to] acknowledge the remarkable bravery of or students and our staff," she said.

"Our highest priority at the moment is caring for our very small community."

A spokeswoman for the Chinese Embassy in Canberra confirmed consular staff were meeting with the university after the attack on Friday but the nature of their involvement is not known.

Student Max Claessen said he was arriving for the next tutorial in the Copland Building when he heard about the attack.

"They seemed a bit traumatised," he said of the class involved in the incident.

"My friend passed on that a male student had got up in the middle of the tutorial with a bat and suddenly gotten very angry and aggravated before striking out at a couple of students and then launching at the teacher."

Mr Claesson said, while students were still reeling from the attack, help had arrived quickly.

"It's not something usual for the ANU; I didn't expect something like this to happen but you can't exactly anticipate someone picking up a...bat in a statistics class.

"My friend had been sitting near him for the past four weeks in class, nothing seemed strange about him."

The federal opposition issued a statement about the attack on Friday. Deputy Labor leader Tanya Plibersek and MPs Gai Brodtmann and Terri Butler said they'd sent best wishes to students caught up in the incident.

"Our thoughts are with the staff and students at the Australian National University following this morning's attack," the statement said.

"Every student and every staff member on campuses across Australia has the right to feel and to be safe.

"Our thanks to the authorities for dealing so swiftly with the matter."

Students received an email from Professor Harding on Friday morning about the incident, assuring them there was no threat to their security on campus.

International student Jessica Zhao said she was shocked by the attack but still felt safe at university overall.

"Canberra is really safe and the ANU is a really safe university," she said.

Fellow student Lucas Ni agreed, adding that students could call security directly on campus overnight.

"I've been studying here for three years, I've never been attacked by another pupil or bothered," he said.

"People are quite peaceful and civilised, not just here but all over Canberra."

Anyone with information was urged to contact police 131 444.