A single fingerprint taken from a mail bomb sent to Rep. Maxine Waters helped investigators get a break in solving a terror plot that targeted senior Democrats and vocal opponents of President Trump, federal officials said.

See:Pipe-bomb suspect Cesar Sayoc charged with five federal crimes

That clue led investigators on Friday to a white van parked outside an AutoZone shop in Plantation, Fla. The van was plastered with images of Trump and Vice President Mike Pence. It also had pictures of liberal figures in crosshairs.

Nearby was its owner, Cesar Altieri Sayoc, a 56-year-old ardent Trump supporter and former male dancer, who federal officials arrested on suspicion of sending more than a dozen bombs around the country.

An expanded version of this report appears at WSJ.com.

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