WOODY ISLAND — Military aircraft have recently been spotted on a Chinese-controlled island in the contested South China Sea, in the first known deployment of fighter jets there since 2017.

CNN reports that to a satellite image from ImageSat International shows China has deployed four Chengdu J-10 fighter jets to Woody Island in the Paracels.

Analysts told CNN that both the placement of the jets out in the open, and the equipment accompanying them indicate they were on the disputed island for up to 10 days.

The planes were also not carrying external fuel tanks, suggesting they were to be refueled on Woody Island.

According to a former operations director at the U.S. Pacific Command's Joint Intelligence Center, the deployment is a statement that China can extend their air power reach over the region.

With the J-10 aircraft's combat range of up to 500 miles or 750 kilometers, this puts the South China Sea and other vital shipping lanes well within reach.

Former Australian Air Force officer and current Griffiths Institute fellow Peter Layton speculated that it could also be early training deployment to get the J-10s ready for an ADIZ declaration.

An ADIZ or air defense identification zone would require aircraft flying over the disputed waters to first notify Beijing.