Bolivia is buying six K-8 jet trainers from Pakistan, for $9.7 million each, to use for anti-drug operations. Actually, the aircraft is a joint Pakistan-China development project. But until recently, all of them were produced in China. Pakistan eventually wants to replace its aging T-38 trainers with 75 or more K-8s. Pakistan received its first 14 K-8s in the 1990s, and now has about 40. Egypt assembled 80 K-8s under license (using Chinese supplied components), and China has exported K-8s to several other countries (often at bargain prices).
The K-8 (also called JL-8) is a 4.3 ton, two seat, jet trainer. It uses a American, Chinese or Ukrainian engines. Originally, China was going to just use a 3600 pound thrust American engines. But after the 1989 Chinese crackdown on pro-democracy forces, the United States cut off the supply of engines. This encouraged China to design a similar engine (the WS-11). But China has had a hard time mastering the precise technologies and manufacturing techniques needed to build jet engines. So it has been buying the Ukrainian AI-25TLK, while it works to perfect its own engine design. About 500 K-8s have been built so far.
The K8 has a cruising speed of 800 kilometers an hour, endurance of four hours and it can carry a 23mm cannon in a bomb like pod, and half a ton of bombs, rockets or missiles. This gives the aircraft combat capability, at least against a foe with few anti-aircraft weapons. Electronics on the JL-8 are minimal, as it's basically a two seat trainer, to prepare fighter pilots before they climb into anything from a MiG-21 to an F-16.