No idea, and I was a little surprised to read that you heard the dispatch for LAPD, if you meant that both the location and nature of the call were voiced.
I've never paid attention to LAFD's dispatch procedures for them, but at LAPD it's always been S.O.P. to not say either "bomb threat" or "bomb scare" over the air. For a bomb threat there will typically be a broadcast on the concerned division's frequency of "North Hollywood units 15A85, 15A85, Incident 3467, Code 3. 15L40, 15L40 Incident 3467 Code 2," and the officers and supervisor will get the details off their MDC. Bomb scares, on the other hand, would usually just go to the MDC without being voiced at all.
For the Bomb Squad's response, the routine from Communications Div is usually a similarly vague "all units" broadcast, that "Units are responding Code 3 from Northeast Division to North Hollywood Division."