Hong Kong authorities have vowed to investigate a mainland Chinese driver under the southbound travel vehicle scheme and may suspend his eligibility after he posted a video of himself using adaptive cruise control illegally in the city on social media. The Transport Department said on Friday that it would issue a warning to the driver while urging Guangdong motorists under the “Southbound Travel for Guangdong Vehicles (Entry into Urban Area)” scheme to use Octopus cards for car park access and...