Trial runs of an artificial intelligence-based on-demand bus service without fixed timetables or routes have started in Tokyo's Shinjuku Ward.

During the trials, an eight-seater bus runs on optimal routes determined by AI, based on factors such as the time and destinations requested by passengers.

A ceremony was held on Thursday to mark the start of the trials, which cover areas mainly around the Shimo-Ochiai and Nakai stations on the Seibu Shinjuku train line.

Officials from the bus company operating the service and the Shinjuku Ward office attended the ceremony.

There are 44 pick-up and drop-off points, including stations, supermarkets and hospitals.

Users can book a ride through a smartphone app or by phone by specifying the time and place they want to get on and off the bus.

The service is available between 9 a.m. and 5 p.m. on weekdays through March 7. The fare for adults is 400 yen, or about 2.5 dollars, while children as well as people with disabilities and their attendants pay half price. Preschool-aged children and younger can ride for free.

Officials say most parts of Shinjuku Ward have a train station or bus stop within a 300-meter radius. But the area served by the new bus service has many slopes and steps.

The officials say they hope the bus service will become a convenient transportation option for elderly residents and parents with young children.