A woman has died after being stabbed inside a mediation room at the Joondalup courthouse on Tuesday morning.
Paramedics performed emergency first aid on the woman before rushing her to Joondalup Hospital but she was unable to be revived.
The stabbing occurred around 10am with a police spokesman describing the 33-year-old's injuries as "serious" at the time.
Janet Lee told the ABC she was in a waiting area at the courthouse next to the mediation room when the woman was attacked.
"We heard a woman's screams, and then a guy came running out shouting [for] security. It was all pandemonium then," she said.
"The staff told us to go outside ... when they came out, the staff were saying 'get towels, get towels, she's been stabbed'.
"And she'd been stabbed in the throat, in an artery, apparently."
Ms Lee said before she left the courthouse she saw a man sitting on the floor surrounded by security officers.
"It was horrible ... we walked away in shock," she said.
A 40-year-old man known to the victim is in police custody assisting detectives with their investigation.
Joondalup courthouse does not have a security checkpoint, but its courts are manned with security guards.
It has been closed for the remainder of the day.
Barrister Gabrielle De Roberto was at the court house as the man was led away by police.
"I saw him in handcuffs being walked out with his head down and she (the victim) was being brought into the ambulance," Ms De Roberto said.
"I could see they were trying to revive her.
"We were put into lockdown at the court for about an hour or so...we weren't allowed to leave the court until the police had got details from everybody.
"Its so very sad, its just so unnecessary."
The incident comes after WA Police Union president George Tilbury last year called for officers in courts to be armed after a number of incidents where people took weapons into courtrooms.
"We have serious concerns that people attending court have been found with a range of weapons," he said in September 2015.
"It shows their state of mind when attending court and the frequency of these incidents is alarming.
"Police officers need to have access to their full range of accoutrements to ensure the safety of themselves and the community.
"The heads of WA's courts have asked for a report to be prepared on this issue and we urge them to ensure the report is prepared as quickly as possible and that safety comes before tradition."
More to come...
