The next batch of Queensland Rail’s troubled New Generation Rollingstock trains have come into service on Monday amid safety concerns.

A total of 27 of the new NGR trains are now in active service, with new services added to the Redcliffe Peninsula and Springfield lines.

However concerns have been raised about the trains being brought into service while an investigation is ongoing into an incident on July 7 when one of the new trains hit overhead power lines, leaving 60 passengers in a second train stranded for over an hour.

QR CEO Nick Easy said on Monday the investigation into that incident was ongoing but he didn’t see a need to delay bringing more of the trains into service.

“That particular train was withdrawn from service, that particular issue was identified and it is safe and back operating on the network,” Mr Easy said.

The investigation has already found there was an issue with one of the train’s pantographs – the cantilevered arms which make contact with the high-powered cables which feed electricity to the train.

Queensland opposition leader Deb Frecklington said it was irresponsible to bring more of the trains into service if there was a question mark over their reliability.

“I think commuters have a right to find out what actually happened in relation to that last incident,” Ms Frecklington said.

The Queensland government has ordered a full inquiry into the procurement of the 75 NGR trains.

The train program was started under the Bligh Labor government and signed signed off on by the Newman LNP government, with the first trains delivered after Labor returned to power in 2015.

The trains were also denied a human rights exemption over the fact they are not fitted with disabled toilets and have limited access for wheelchairs.

Transport Minister Mark Bailey said rectification works, including to improve disability access, are ongoing.

“This has been done through a series of co-design workshops to ensure that the modified trains will meet functional requirements for all customers, as well as meeting the compliance standards required by the Disability Standards for Accessible Public Transport,” Mr Bailey said in a statement.

Work to fix the problems with the trains, from Canadian company Bombardier, is being carried out at the railyards in Maryborough, northwest of Brisbane.