A private, unmanned spacecraft has returned to Earth after delivering its first official cargo shipment to the International Space Station.

The Dragon capsule, built by California-based SpaceX, splashed down Sunday in the Pacific Ocean several hundred kilometers off the southwest U.S. coast.

It brought back about 750 kilograms of cargo, including hardware, science experiments and medical samples collected from the astronauts aboard the space station.

The cargo is being transferred to the U.S. space agency NASA, which has a deal with SpaceX to make at least 12 trips to supply the space station in a contract worth $1.6 billion.

The next supply mission is scheduled for January.

Russia's Soyuz capsule is the only other spacecraft that returns anything to Earth from the station, and has little room for cargo because it is used for astronaut transport.