I think the sentences are pretty equivalent like they are. "Da" is used to point to the direction from which someone is coming, if that someone is visible (but not recognizable) ("Sieh mal, da kommt irgendwer. Erkennst Du, wer das ist? Kennst Du ihn?"), but the sentence could also be said if you just hear someone or something ("Hörst Du das? Da kommt irgendwer!"). Do you have a more idiomatic expression for this in English?
With short colloquial, idiomatic expressions like this, translation is more about swopping an idiom in one language for one that you'd use in the same circumstances in the other. I think you are more likely to use DL's offering than to actually literally translate "da" as "there" in this one ............. but it's not wrong!