Luke 13:4

Or those eighteen, upon whom the tower in Siloam fell, and killed them, think ye that they were offenders above all men that dwell in Jerusalem?

The tower of Siloam ... points to some construction with the pool of that name, and having to do with the aqueduct that brought water into it, and perhaps also with the Roman fortifications of the city. Josephus wrote that "Pilate expended the sacred treasure which is called corban upon the aqueducts, whereby he brought water from a distance of four hundred furlongs."[8]

Upon the presumption that the eighteen men were workers on the construction when the tower fell, it is easy to see how the Jews would have accounted them especially sinful; for not only were they working for the hated Romans, but they were being paid with money that Pilate had robbed from the temple treasure. However, Jesus rejected the notion that such conduct was the reason they were killed.

Significantly, this terrible accident was introduced into the conversation, not by his hearers, but by Christ himself; but he used it in exactly the same manner as he used the other incident, demanding of all people (and specifically including Israel) that they should repent or perish.