United Technologies' (NYSE:UTX) Pratt & Whitney Canada group pleaded guilty on Thursday to illegally selling military technology to China for use in an attack helicopter and will pay more than $75 million.

Shares of United Technologies slumped more than 3% Thursday afternoon.

Pratt Canada exported the advanced defense technologies to China from 2002 through 2004. The software was used to develop the Z-10 Chinese military helicopter, United Technologies said in a filing.

It has been illegal in the U.S. to export defense articles and associated technical data to China since June 1989 following the massacre at Tiananmen Square by the military of the People's Public of China.

The DOJ said that dating back to the 1980s, China has sought development of a military attack helicopter and beginning in the 1990s, after Congress had imposed the prohibition on exports to China, tried to develop the military helicopter under the guise of a civilian helicopter program in hopes to secure Western assistance.