A jury in Hawaii has convicted a former US engineer of selling military secrets to China.
Noshir Gowadia, who helped design the propulsion system for the B-2 bomber, was found guilty on multiple counts - including conspiracy and money laundering.
Indian-born Gowadia, 67, could be sentenced to life in prison.
The case is one of a series of major prosecutions targeting alleged Chinese spying in the US.
According to prosecutors, Gowadia helped China to design a stealth cruise missile.
It involved an exhaust nozzle that would evade infrared radar detection and US heat-seeking missiles.
Gowadia was accused of travelling to China between 2003 and 2005 while designing the missile.
He was said to have been paid $110,000 (£69,000) - money that was used to pay off a mortgage on a luxury home on the island of Maui.
In his defence, lawyers said it was true that Mr Gowadia had designed an exhaust nozzle for China - but that it was "basic stuff" based on unclassified information that was publicly available.
Gowadia, who was born in India, moved to the US in the 1960s and became a citizen about a decade later.
He has been in custody for nearly four years and faces life in prison when he is sentenced in November.
He was found not guilty on three counts of communicating national defence information to help a foreign nation.