NOBODY alerted authorities while a woman in her 50s was being allegedly indecently assaulted on a nightmare train journey last week, it has been revealed.

White Gum Valley resident Jamie Hansen (31) has since been charged with indecent assault, brandishing a weapon and threatening to kill train-goers, but the incident has prompted a victims’ advocate to call for more security guards on trains.

Mr Hansen was travelling on a city-bound Thornlie line train at around 7am on August 5 when police allege he became “erratic, shouted abuse and banged on windows before removing a 30cm knife from a bag”. 

The alleged victim was sitting in a corner seat, trapped by Mr Hansen when he indecently assaulted her.

“The man allegedly took the knife from his waistband and waved it at other passengers threatening to kill them before going back to the woman and indecently assaulting her again,” a police media release reports.

Mr Hansen jumped on and off two city-bound trains before being arrested after a chase.

A spokesperson for the Perth Transport Authority confirmed no one on the train attempted to alert authorities as the situation unfolding in the carriage, but advocate Nicki Hide says bystanders might simply have been in shock. 

“Fear for their own safety and vulnerability is compounded by the realisation they are not trained in negotiating with hostile offenders, especially those threatening or using a weapon during an assault,” she said. 

Only once Mr Hansen got off at Victoria Park were WA Police informed by a ticketing officer who had witnessed him abuse a security guard and threaten other members of the public. 

The PTA told the Herald the incident could have been de-escalated more efficiently if witnesses on the train had alerted authorities as it was happening. 

“We would encourage anyone who witnesses violent or antisocial behaviour to tell a staff member, press one of the emergency buttons on the platform, or alert the train driver by pressing the intercom button if it is safe to do so. Passengers are also able to call the PTA’s emergency incident number (9220 9999), which is monitored 24/7,” the department said in a statement to the Herald.

But Ms Hide says Transperth should step up its security game. 

“There must be a minimum of three highly trained security officers on every single train,” she said.

“They must be able to actively monitor all carriages on that train, and proceed immediately to whichever carriage they are required.” 

The PTA argues its security system – including 366 security staff – is “the envy of the nation’s public transport providers”.