The windows of a restaurant are boarded up in preparation for possible election related protest in Washington, D.C., the United States, Oct. 31, 2020. (Xinhua/Liu Jie)

The door and windows of an investment firm are boarded up in preparation for possible election related protest in Washington, D.C., the United States, Oct. 31, 2020. (Xinhua/Liu Jie)

The door and windows of Department of Veterans Affairs are boarded up in preparation for possible election related protest in Washington, D.C., the United States, Oct. 31, 2020. (Xinhua/Liu Jie)

The windows of a flower store are boarded up in preparation for possible election related protest in Washington, D.C., the United States, Oct. 31, 2020. (Xinhua/Liu Jie)

Fences are added in front of the St. John's Episcopal Church in preparation for possible election related protest in Washington, D.C., the United States, Oct. 31, 2020. (Xinhua/Liu Jie)

Birds rest on a stopped crane near the White House in Washington, D.C., the United States, Oct. 31, 2020. (Xinhua/Liu Jie)

The windows of a retail store are boarded up in preparation for possible election related protest in Washington, D.C., the United States, Oct. 31, 2020. (Xinhua/Liu Jie)

The windows of a flower store are boarded up in preparation for possible election related protest in Washington, D.C., the United States, Oct. 31, 2020. (Xinhua/Liu Jie)