SpaceX has launched its first recycled cargo ship to the International Space Station.

An unmanned Falcon rocket lifted off Saturday from Florida's Kennedy Space Centre with a Dragon capsule that made a station delivery nearly three years ago. When this refurbished Dragon reaches the orbiting lab Monday, it will be the first returning craft since the now-retired shuttles.

The same capsule is back for take two after a few modifications and much testing.

The first-stage booster used Saturday is new, but as is now the custom, will attempt to return to Cape Canaveral following liftoff. It's all part of SpaceX's long-term effort to save money through reusability.

Besides the usual supplies, the 2,721 kilogram shipment includes mice and flies for research.

The flight was delayed two days by thunderstorms.