Come across crash ... (3,4)
I believe the answer is:
run into
I believe this clue is a double definition.
'come across' is the first definition.
(synonyms)
'crash' is the second definition.
(thesaurus)
(Other definitions for run into that I've seen before include "Meet (someone) unexpectedly" , "Encounter (someone)" , "Meet accidentally on the trot?" , "charge?" , "Encounter by chance - or collision?" .)