That's affirmative. Charles Whitman killed 12 people from a 28-story observation tower at the University of Texas. From distances of up to 400 yards.
12 seconds sound clip from the Jaws (1975) movie soundboard.
You can hear this line at 00:31:07 in the Blu-ray version of the movie.
Quote context
[...]
- Do any of you people know who Charles Whitman was?
- None of you dumb-asses knows?
- Sir, he was that guy who shot all those people from that tower in Austin, Texas, sir.
- Anybody know who Lee Harvey Oswald was?
- That's right. And do you know how far away he was?
- Sir, he was pretty far. From that book-suppository building, sir.
[...]