Voting in multiple battleground states was disrupted on Tuesday as numerous polling places received death threats, many of which the FBI said it determined had ties to Russia, prolonging polling place hours and raising the specter of election interference.

The U.S. saw a rash of discredited bomb threats called in at polling places in multiple states on Election Day, in some cases spurring the need for extended voting hours. Faulty bomb threats were called into at least five states,

An already heated presidential race faced further strain from a string of reported bomb threats in battleground states—causing some delays on Election Day.