Roswell police and the FBI are investigating after envelopes with “white powder” were found in congressional candidate Karen Handel’s mailbox and at four others in her subdivision.

The call came in about 1 p.m. for Roxburgh Drive off Old Alabama Road in the Willow Springs neighborhood, police said.

“This afternoon we had some suspicious packages delivered to our house and to our neighbors,” Handel said in a statement. “The packages contained threatening letters and a suspicious substance. The police were quickly notified and the street is now being blocked off. We will continue to coordinate with law enforcement as necessary.”

Test results for the powder are pending, FBI Atlanta spokesman Stephen Emmett said. Roads in the area were blocked off by authorities, and police are searching other mailboxes for possible suspicious packages. Firefighters and emergency crews are also on the scene.

One woman was exposed to the powdery substance and was reported to be all right, Channel 2 Action News reported.

Melissa De Feis Lentz, a stay-at-home mom who lives down the street from Handel, provided a copy of a letter that neighbors received. It said “your neighbor Karen Handel is a dirty fascist” expletive, and to take a “whiff of the powder and join her in the hospital.”

Lentz said it has shaken up the neighborhood.

“It's definitely gotten too crazy. It's sad that this is the world we live in now,” she said. “And I know neither side would condone what's happening. Even if it's an idle threat it's way too much. No one should speak that way about another human being.”

Handel is the Republican candidate for Georgia's 6th Congressional District. She and Democrat Jon Ossoff are in a runoff election Tuesday to replace the seat left vacant by Tom Price when he was named Health and Human Services secretary.

Ossoff campaign manager Keenan Pontoni told The Atlanta Journal-Constitution that his campaign has also received multiple threats of violence in recent days, which he said have been reported to police. The Ossoff campaign hired a security detail on Thursday as well as a result of the escalating tensions.

“These recent events speak to the need for a redoubled commitment to civility and unity,” Ossoff said in a statement. “The overwhelming majority of Americans want decent and civil political dialogue, and candidates for office and elected leaders must continue to call for calm and unity, even when there are intense differences of opinion.”

Handel took to Facebook to thank her supporters and law enforcement.

"It is frustrating that my neighbors have been affected in this way," she said. "(My husband) Steve and I know that running for public office often brings these kinds of challenges, but our neighbors did not sign up for this. For someone to bring them into this race in this way is despicable.

“At the end of the day, however, we are grateful. We have great neighbors who extended many acts of kindness. Our first responders are awesome. Even in this highly charged environment, Steve and I feel safe.”

It has been a tumultuous week for Handel. A Facebook user by the name of James Thomas Hodgkinson, the Illinois man said to be the alleged shooter at Wednesday's GOP baseball practice in Virginia, posted an explicit comment involving Handel to the social networking website.

Suspicious letters containing white powder were also sent news stations FOX5 and 11Alive, Emmett said, but made not mention of whether the two incidents were connected to threats toward Handel. FOX5 reported

Any media outlets receiving such packages are asked to follow the appropriate HAZMAT protocols and, after appropriate reporting, please ensure that the FBI Atlanta Field Office is contacted as well.

— Please return to AJC.com for updates.

Staff writer Raisa Habersham contributed to this story.