The US Department of Homeland Security declared a nationwide terrorism alert Wednesday, citing the potential threat from domestic anti-government extremists opposed to Democrat Joe Biden as president.

The alert said extremists could undertake attacks against elected officials and government facilities, “emboldened” by the deadly January 6 assault on Congress by angry supporters of former president Donald Trump.

The alert came as the authorities in California charged a Trump supporter and follower of a far-right militia group with possession of five home-made pipe bombs, alleging he intended to attack Democrats.

The National Terrorism Advisory System Bulletin said the threat of attacks could persist for weeks, in the wake of Biden’s January 20 inauguration and as Trump faces an impeachment trial in the Senate for “incitement of insurrection” for allegedly encouraging the assault on the US Capitol.

“Information suggests that some ideologically-motivated violent extremists with objections to the exercise of governmental authority and the presidential transition, as well as other perceived grievances fueled by false narratives, could continue to mobilize to incite or commit violence,” the Department of Homeland Security said.

“DHS does not have any information to indicate a specific, credible plot,” it said.

“However, violent riots have continued in recent days and we remain concerned that individuals frustrated with the exercise of governmental authority and the presidential transition... could continue to mobilize a broad range of ideologically-motivated actors to incite or commit violence.”

- Over 150 arrested -

The alert came two days after the Pentagon said thousands of National Guard troops who came to Washington for Biden’s inauguration would remain in the capital through March due to FBI intelligence on potential threats.

The DHS alert said threats had grown since last year from domestic violent extremists motivated by Covid-19 restrictions, Biden’s defeat of Trump in the November election, police brutality and illegal immigration.

On Tuesday, the Justice Department said it had arrested more than 150 people over the attack on the Capitol and was investigating hundreds more.

Increasingly the investigations are focused on conspiracy and sedition charges, which can bring up to 20 years in prison, said Michael Sherwin, the acting federal prosecutor for Washington.

Three linked to the extremist Proud Boys and Oath Keepers groups have been charged on those grounds. Their case is significant, Sherwin said, because “it shows militia groups actively involved in planning and breaching the Capitol.”

The FBI continues to search for a person or persons who placed two pipe bombs near the US Capitol on January 6.

The bombs were real but never detonated, and the FBI has offered a $75,000 reward in the case.

In San Francisco Wednesday the Justice Department announced charges against Ian Benjamin Rogers, 43, for possessing five pipe bombs and the materials to make more.

An FBI affidavit said Rogers was linked to the Three Percenters violent anti-government group and had 49 guns and thousands of rounds of ammunition in his Napa Valley home and business.

The affidavit said messages on Rogers’ phone indicated he believed Trump’s claim that Biden’s November 3 election victory was rooted in widespread fraud.

The messages showed “his intent to attack Democrats and places associated with Democrats in an effort to ensure Trump remained in office,” the affidavit said.

The messages indicated he was considering attacking the office of California Governor Gavin Newsom, a Democrat, and also of Twitter and Facebook, which blocked Trump’s postings and those of right-wing extremists. (AFP)

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