Perak traffic police chief Supt Wan Jamil Wan Chik said apart from the driver, the bus company had also been issued with 63 summonses.
He also said that the express bus driver, who was arrested by the police yesterday, was tested negative for drugs.
Wan Jamil added that the police will apply for a remand order later today to detain the 51-year-old bus driver for further investigations.
Meanwhile, The Star Online reported that the express bus, which was heading from Penang to Kuala Lumpur, had experienced a technical problem as it was travelling down a slope near the site of the incident.
“The brakes weren’t functioning well. As a result, the bus headed down the slope at high speed and rammed into 10 other cars in front,” said Ipoh OCPD Assistant Commissioner Sum Chang Keong as quoted by the portal.
He also confirmed that a passenger in one of the cars, a 21-year-old girl, suffered pain in the stomach area.
Yesterday, a video captured on a surveillance camera which has since gone viral on social media, showed the bus exiting the Menora Tunnel at high speed before ramming into several vehicles.
The accident reduced traffic to a crawl over 11km stretch.