Almost 60 passengers were left trapped underground after an issue involving one of Queensland Rail's (QR) New Generation Rollingstock trains led to damaged power lines, leading to widespread delays.
In an incident set to fuel more criticism of the new trains, electrical contact between a train and overhead lines caused damage to the power supply on Saturday night.
It resulted in another train on the Brisbane airport line breaking down in the tunnel between Roma St and Central stations at around 8.30pm.
After being stalled for more than an hour, passengers had to be evacuated via an emergency exit, with one person reportedly needing treatment for anxiety.
The power issue was still being resolved by 1pm on Sunday, with services to Brisbane's south and east rerouted to avoid inner-city station South Brisbane.
Southbound trains between Roma St and Moorooka were replaced by buses, with delays felt on all other services as they passed through the city.
QR has apologised to customers.
"On inspection, electrical contact between a New Generation Rollingstock train and the overhead powerlines resulted in damage to the train and power supply," QR spokesman Nick King said in a statement.
"Works are now underway to move the train and repair 1200 metres of damaged overhead equipment.
"The contact between the train and overhead line did cause minor electrical sparking."
QR said it was yet to be determined if the NGR train caused the power problem.
The incident is the latest in a series of problems associated with the new trains, which have been delayed and flawed in design after failing to meet Australian requirements around disability access.
The procurement process started under Anna Bligh's Labor government, but was signed off by Campbell Newman's LNP government, with the first trains delivered after Labor returned to power in 2015.
Premier Annastacia Palaszczuk was transport minister at the time the process was started.
Robert Dow, from the Rail Back on Track advocacy group, told AAP they're worried there's something wrong with the new trains not properly interacting with existing overhead infrastructure.
"We have to find out, do these new trains have a propensity for dewirements (sic) that the old trains didn't have," he said.
