Two Chinese Sukhoi Su-30 jets have conducted an “unprofessional” intercept of a US aircraft, the US military said.

One of the Chinese jets came as close as 150ft (45m) to the US WC-135 plane and flew upside down above it, according to US officials cited by CNN.

The US says the plane was on a mission to detect radiation in international airspace over the East China Sea.

Tensions have repeatedly raised over US activity near the resource-rich international waters off China’s coast.

Taiwan National Day Celebration