As people head to the polls Tuesday, concerns linger over safety amid an ISIS threat against Texas, Virginia, and New York as well as the contentious nature of the election.

Multiple law enforcement agencies--including Houston Police--told us Monday night they don't provide or won't have a presence at polling places unless they are called but election officials are keeping a close eye on things.

They're even watching the threat from ISIS--a group calling for the "slaughter of Americans" on election day

"It's more important for the voters to overcome the fear of something happening when there's no notice of anything happening," Stanart said. "It's more important for them to go vote."

Stanart says police officers can be hired as security but some communities believe men and women in uniform are a form of intimidation. He adds that he doesn't know of any violence at the polls.

"It's really been a calm election," Stanart said. "Early voting has really been calm. The incidents have been small. I don't know of any fights that have broken out."

May Walker, constable of Harris County Precinct 7, said her deputies will be periodically be passing by the 85 polling stations in her area to ensure everything runs smoothly.

"We are very aware that they might have some kind of encounters for long lines," Walker said.

Stanart said police might be called in to handle traffic if voting lines get out of control.

He said there's been a coordinated effort with HPD, the Harris County Sheriff's Office and constables months before Tuesday to work out any problems.