The ac in question was built by taking the back end of a damaged finnish c model Hornet and mating it with the front end of a damaged canadian b or d model. So they turned a single seater into a two seater and where very happy. The job took a couple of years and was finnsihed last september. Everybody involved in the project(Finnish air force, Patria and Boeing) reported it as a great success.
Local media reports that the flight was only the third testflight of the "new" a/c. Reports allso say that the plane was put into a tail slide at an altitude of 10km. It failed to recover properly and the crew ejected at about 4,5km. The plane was flown by a 32 year old captain and the other crew member was a 44 year old liutenant-colonel. They both suffered from fractures and where treated at Tampere university hospital.
Here is a link to a finnish newspaper... Text in finnis but some pictures of the crash site.
Turma-Hornetin lentäjät joutuivat leikkaukseen - Suomi - Uutiset - Ilta-Sanomat