Tesla Inc. shares climbed after the automaker rolled out its long-promised driverless taxi service to a handful of riders, a modest debut for what Elon Musk sees as a transformative new business line.

The service kicked off as scheduled aboard Tesla's Model Y vehicles, with customers paying a $4.20 flat fee to ride.

Analysts said the "low-key" robotaxi launch highlights Tesla's big bid to compete with existing self-driving taxi operators in the US and China, as the sector grows. Musk congratulated Tesla's artificial intelligence and chip design teams on the launch in a post on X, writing that it was "culmination of a decade of hard work".