“There have been concerns raised about the possibility of civil unrest, and those are concerns raised on both sides, for different reasons, and because of that, we’re paying particularly close attention to that possibility,” the official said. “I think that we would be remiss if we didn’t take the monitoring of election security and integrity particularly seriously.”

Those at the command center, including civil rights and national security officials, will monitor news accounts of any high-profile incidents, as well as reports from U.S. attorneys or others in the field, and determine how the federal government should respond, the officials familiar with the matter said. In addition to watching for possible violence, officials will assess possible cyberthreats to election infrastructure and reports of voter fraud or intimidation, the officials said.

Plans to use the command center had been underway before Tuesday night’s presidential debate, when Trump called on his supporters to monitor the polls and notably declined to condemn white supremacists, saying the far-right Proud Boys group should “stand back and stand by.”