Video report by ITV News Washington Correspondent Robert Moore
All 50 US states are on alert with the capital on lockdown ahead of the inauguration of incoming president Joe Biden on Wednesday.
The Pentagon has authorised 25,000 troops to be deployed to Washington DC in what is some of the tightest security ever seen.
The FBI is warning of possible armed protests following a recent attack on the US capitol.
Heightened security reflects fears that violent extremist groups are targeting the Washington DC, with threats ranging from armed insurgents to possible attempts to plant explosive devices at so-called soft targets.
But as Washington begins to resemble an armed camp, with more than 25,000 Guard due in the city by early next week, concerns about violence at state capitals has grown.
While much focus is on Washington, state capitals also fear violence, reports ITV News Correspondent Emma Murphy in Richmond, Virginia
Oregon Governor Kate Brown said she turned down the federal request to send at least 100 more National Guard troops to DC.
“I didn’t think that we could safely fill that commitment,” Brown said.
Oregon has already agreed to send 30 to Washington, but state leaders are worried about violence at the state capitol in Salem.
Others agreed, setting off a dizzying torrent of military flights and convoys into the region.
Many governors were willing to help, but they made it clear that their own state capitals were their priority. Some agreed to send more, while others couldn’t. And the numbers varied widely.
Pennsylvania Governor Tom Wolf doubled his initial commitment of 1,000 to 2,000. Other states were able to scrape up an additional dozen.
After reviewing the threats to its own state, Minnesota decided it could significantly increase its contribution and will send 850 Guard rather than the 130 initially tapped to go.
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