"Footage from the train and station cameras has been saved for police," Hannan said.
The train manager assisted the family and took full descriptions of the three people, who were spotted on another train.
Police were called again, and they were monitored by staff until police arrived.
Cortese, best known for his role as Hayden Peters on Outrageous Fortune and Mac on Nothing Trivial, recounted the incident on Facebook.
"Kees and I were on one of our regular train trips so he could make VLOGS with his iPad. It's a regular autistic pattern to like trains. He sits a couple of seats in front of me and loves these trips," he said.
"At Middlemore two men and a woman got on the train and sat around us and acted very intimidatingly to both me and my 10-year-old."
He described them as "big heavy-set NZers with very bad facial tattoos".
"Within seconds Kees was agitated, panicking and crying because his iPad had been lifted," Cortese said.
"I then had the pleasure of one of them standing over me and asking me 'what the f... was I looking at'. They got off the train at Papatoetoe and abused me through the window."
Cortese said his son has lost his iPad and was upset.
He has given police the photos and video he took of the men and woman.
"I'm not going to post the photos because the police have them but I'm really disappointed I couldn't prevent my son from being upset," Cortese added.
"That's what dads do."
When approached for comment, a police spokeswoman said: "In general police are not able to respond to request which seek to establish whether specific individuals are or have been under police investigation.
"Additionally anyone who makes a complaint to police has the right to privacy."
AT and its operator Transdev said they took security on the train network seriously and were continually working with the police.
More than 200 transport officers were being recruited as part of the SaFE programme aimed to increase passengers' security and safety on trains and at rail stations.
The officers are being trained and the first group will be on the job from next month.
More stations will also be gated as part of the programme, and gates have recently been installed at Otahuhu and Henderson stations, with more to be completed by mid-2018.
Cortese has been contacted for comment.
