This was true in the early 1990's but I rarely hear a car alarm these days.

There was one particularly annoying car alarm that was popular in the 1990's that had a sequence of "police/ambulance siren" sounds.

Bieww Bieww Bieww Bieww, oooo eeee oooo eeee, rrr rrr rrr rrr, ee oo ee oo, booooooooup booooooooup booooooooup booooooooup, oooooooo eeeeeeee oooooooo eeeeeeee <repeat>

Or something like that.