The family of a man accused of storming a south-side government office with a chainsaw has apologised to those caught up in the mayhem.
But his mother said the incident could have been avoided if the mental health system had stepped in earlier.
A 34-year-old Dickson man remains in police custody after he allegedly attacked the Department of Human Services' Greenway office in Cowlishaw Street with a running chainsaw on Thursday afternoon.
The man, who is understood to be a former DHS employer, allegedly smashed a glass security door of the office, causing extensive damage.
Terrified staff reportedly dashed for cover upon hearing of the intruder, with some cowering in cupboards before escaping the building to the safety of the Tuggeranong library.
A stream of triple-0 calls alerted police to the drama and the man surrendered when officers arrived shortly before 4pm.
No one was injured during the incident and staff have reportedly been offered counselling.
His mother, who wished to remain anonymous until family and friends could be notified of the incident, tearfully said the family were sorry for her son's behaviour.
"I would like to extend our regret and apologise to the individuals that have been affected by the incident.''
She said her son's mental health had gradually declined in recent years, to the point where he had cut off contact with his friends and family.
She said he was a client of Mental Health ACT and had previously been taken into care.
The family had been alerted to impending trouble earlier on Thursday when the man sent a concerning text message to his flatmate.
The mother said the flatmate contacted authorities but was told it was not an emergency. She said her son had never been a violent person.
"The mental health service has failed [my son] in his care and had an opportunity to prevent this incident," the mother said.
"The mental health team have been contacted on numerous occasions by [my] family concerned for [his] mental state and have on the majority of occasions failed to act on information … for at least the last two years.
"Mental health services have been contacted in the last two weeks in regard to communications from [my
son] and related concerns he was acutely unwell and yet again failed to act on those concerns."
The man has been charged with possessing an offensive weapon, damaging Commonwealth property and acting to cause public alarm. An aggravated burglary charge has been dropped. The accused is expected to face ACT Magistrates Court on Saturday.
Police have urged anyone who may have witnessed the incident and has not already spoken to them, or has information which may assist police, to contact Crime Stoppers on 1800 333 000 or through the website act.crimestoppers.com.au.