Police said three women including the lecturer and one man received serious injuries and were taken to hospital. The ANU spokesperson said there was no ongoing threat to public safety.
A man has been arrested after allegedly assaulting four classmates at a Canberra university.
"At around 9:15am this morning, a student entered an ANU classroom and assaulted four other students".
Several people were injured in the attack and emergency services remain on the scene.
"There is no indication of motive and this is now a police matter".
ANU students received an email from the university alerting them of the incident and assuring them that the perpetrator was removed from campus and detained by police.
"I believe one of the students has actually taken the baseball bat from the student with it and run away with it, and then returned later and given it to police".
Professor Hughes-Warrington said the event was "shocking for everyone" considering Canberra was a caring community.
"If you or someone you know is in distress or needs assistance, there is help available".