The wooden horse

Hyginus: Fabulae
Laocoon

Laocoon, son of Capys and brother of Anchises, had married and raised a family against the will of Apollo; he was now chosen by lot to sacrifice to Poseidon on the shore.

Apollo took the opportunity to send two snakes across the bay from Tenedos, which killed Laocoon's sons, Antiphas and Thymbraeus. When Laocoon tried to come to their aid, the snakes coiled around him and killed him too.

The Trojans concluded that this took place because Laocoon had hurled a spear at the Trojan horse.