Passers-by heard a man shouting death threats and a toddler screaming.

But, when police arrived at a Perth home on Wednesday morning, they found the only injuries were to a spider.

Multiple police units responded with lights and sirens after a caller walking past a home heard a man repeatedly shout: "Why don't you die?"

It's not clear what breed of spider caused the Perth man to scream in fear. Credit:Gary Cranitch

The caller, who did not know the family living at the house but had seen them a few times, told Wanneroo police they could not hear the female occupant.