The escalator apparently had been installed without a valid certificate of fitness, officials said.
The operator, who was running the escalator despite not maintaining it or renewing its certificate of fitness (CF), could face up to a 20 lakh rupees fine or two years' jail if found guilty, said Department of Occupational Safety and Health Malaysia (DOSH) director-general Mohtar Musri.
"We checked the safety devices they had on the escalator and the CF. Based on our investigations, they did not comply," Musri said.
It caught the fabric of his pants and the tip of his penis. Fire and Rescue Department officers took about half-an-hour to dislodge the boy from the escalator using crowbars.
Mohtar said there was still a high chance the incident could have happened even if the unsupervised boy was on a certified safe equipment.
"He was sitting on the step, which is not a safe way to ride an escalator. You are not supposed to do that," he said. The boy is reported to be recovering.
In February, a three-year-old had part of his foot severed after a similar incident.
Authorities have advised parents to pay closer attention to their children while using the escalator.
