Bike-sharing service operators are locking horns with each other as the service catches on with consumers.

Firms participating in the Bicycle City Expo 2018 that kicked off Tuesday in Tokyo said competition is expected to become more heated in the coming years. At the same time, they expressed hope the market will grow.

A number of firms have made forays into the Japanese bike-sharing business over the past year, including Mercari Inc., a Tokyo-based flea-market app operator, and Chinese bike-sharing giants Ofo and Mobike.