That is what Mr. Saldhana was saying on TV last night. BTW, it was him and some others who had filed a petition against DGCA's recommendation to the courts for going ahead with the Mangalore new airport citing operational issues and the hill location. His views at that time were shot down.
So, till the black box gets de-coded, nothing can be arrived at. After giving it a deep thought, it could have been (just contemplating),
The wheel brakes of the aircraft had failed. The wheel brakes are usually applied at the last ie. when the aircraft has significantly lost speed on landing, by using the wind brakes set on at the rear part of both the wings. This portion, on application, maintains a perpendicular profile as against the parallel aerofoil of the wing, which causes severe wind resistance, which in turns act as a wind brake. I believe this had worked normally.
Logically, the wheel brakes could have failed. So, the aircraft just kept on going at a moderate speed and tumbled off into the jungle. At low speeds, the wind brakes are ineffective.
......... I could be wrong though .......... The airstrip being shorter, added to this problem.