Yup. Generally speaking, a condition of probation is that the probationer refrain from breaking any more laws.
His probation could be revoked and he be re-sentenced up to the maximum jail/prison term of the original charge. Given that he got 10 years of probation, I bet that he would be looking at quite a bit of prison time.
He may plead not guilty at his court appearance and request a PD, if eligible.
Better they hear it from him first.

