A Chinese military aircraft was spotted on a disputed island in the South China Sea late last month, according to a US think tank that monitors activity in the region, and the move is unlikely to go unnoticed by Beijing’s neighbours, analysts said.

Collin Koh, a research fellow at the S. Rajaratnam School of International Studies at Nanyang Technological University in Singapore, said that the military plane seen in the latest photographs appeared to be a “normal airlifter”.

He was referring to the fact that although the People’s Liberation Army classifies the Y-8 as a transport plane, capable of carrying more than 120 passengers, several of them have been retrofitted with intelligence gathering equipment.

“Seeing military-grade airlifters in the disputed area is not unusual,” Koh said, adding that similar aircraft from the Philippine and Malaysian military had been spotted in the region.

“The only [notable] thing is that because of the scale of the airstrips on China’s artificial islands … they could support much larger airlift operations, [for example] during a large-scale military build-up.”

The strips are big enough to accommodate China’s Y-20 heavy airlifters, H-6 strategic bombers and fighter jets, he said.