Tracy Pierson breaks the news in the link above.
UPDATE (N): However, per the DB Sports Twitter:
A team spokesman says report on Nelson's dismissal is inaccurate. Howland holds his weekly press conference this afternoon. More to come.
UPDATE II (N): From DB Sports:
UCLA suspends Nelson indefinitely from team for conduct "unbecoming a member of the UCLA basketball team." No timetable for his return.
More comments from Howland on DB twitter account.