Transport Commissioner Rosanna Law said on Thursday that she is confident that an electronic auto-toll system, HKeToll, will be able to handle traffic at one of the busiest tunnels in Hong Kong.

Drivers using the Lion Rock Tunnel will no longer need to stop at toll booths to pay fees from May 28, while the new system will also be in place at the Shing Mun Tunnels from May 21.

Law said HKeToll, which was introduced in the Tsing Sha Control Area earlier this month, can handle 86,000 vehicles an hour.

"The three tunnels, Shing Mun, Tsing Sha and Lion Rock... we are talking about merely 16,000 vehicles per hour at their busiest time during a day. So 86,000 is already more than five times the capacity. That's why we say the system is completely capable," Law said.

The transport chief also said the department had received more than 50 complaints about HKeToll as of Monday, including five involving the alleged use of fake car plates.