A US court has sentenced an aerospace engineer to over 15 years in prison for spying for China.

Greg Chung Dongfan, a Chinese-born US citizen, was found guilty last year of stealing and selling documents from aviation manufacturer Boeing. The information reportedly included information on the space shuttle programme.

The 73-year-old engineer worked for a number of American aerospace companies for 30 years. When he was arrested in 2006, the FBI found 300,000 pages of confidential information at his home. He denies spying for China and says he was using the documents as the basis for a book.