Says Sarkar was PhD student since 2006, which suggests great difficulty in finishing the program (4-6 yrs. is typical). Sarkar wrote a brief blog post claiming the Prof. stole his code and gave it to another student:
http://heavy.com/news/2016/06/mainak-sarkar-william-klug-suspect-ucla-professor-shooting-blog-post/
Bitchin’ because of stolen code? Damn...that’s just practice for working at Microsoft.