Collocations for siren - noun

approaching
The cars had stopped at the sound of the approaching siren.

distant
blaring, wailing
the blaring sirens of ambulances and police cars

air-raid, ambulance, emergency, fire, police, tornado (esp. AmE), warning

put on, sound, switch on
The ships all sounded their sirens.

hear

go (BrE), go off, sound, start, start up
blare, scream, wail
The ambulance sped off with its siren wailing.