Officers in Washington DC arrested a Virginia man who tried to pass through a Capitol police checkpoint carrying fake inaugural credentials, a loaded handgun and more than 500 rounds of ammunition. The man, identified in court papers as Wesley Allen Beeler, was driving a pickup truck with several firearm-related bumper stickers, including one that read: “If they come for your guns Give ‘Em your bullets first,” the papers said. Beeler presented an “unauthorized inauguration credential” at a Capitol police checkpoint on Friday evening, court papers said. He was scheduled to appear in court on Saturday. His court-appointed lawyer could not immediately be reached for comment. Capitol police officials could not immediately be reached for comment. Responding to news of the arrest, the Democratic US representative Don Beyer of Virginia said the danger was real and the city was on edge as Joe Biden’s inauguration approaches. “Anyone who can avoid the area around the Capitol and Mall this week should do so,” Beyer wrote on Twitter. US law enforcement officials are gearing up for pro-Trump marches in Washington and all 50 state capitals this weekend, erecting barriers and deploying thousands of national guard troops to try to prevent the kind of violent attack that rattled the nation when Trump supporters stormed the US Capitol on 6 January. The FBI warned police agencies of possible armed protests outside all 50 state capitol buildings starting on Saturday and through Biden’s inauguration on Wednesday, fueled by supporters of Donald Trump who believe his false claims of electoral fraud. Michigan, Virginia, Wisconsin, Pennsylvania and Washington were among states that activated their national guards to strengthen security. Texas closed its capitol through inauguration day. Steve McCraw, the director of the Texas Department of Public Safety, said in a statement late Friday that intelligence indicated “violent extremists” could seek to exploit planned armed protests in Austin to “conduct criminal acts”. The attack on the US Capitol in Washington was carried out by Trump supporters, some of whom planned to kidnap members of Congress and called for the death of the vice-president Mike Pence as he presided over the certification of Biden’s victory. The Democratic leaders of four congressional committees said on Saturday they had opened a review of the events and had written to the FBI and other intelligence and security agencies to find out what was known about threats, whether the information was shared and whether foreign influence played any role. “This still-emerging story is one of astounding bravery by some US Capitol police and other officers; of staggering treachery by violent criminals; and of apparent and high-level failures – in particular, with respect to intelligence and security preparedness,” the letter said. It was signed by the House intelligence chair, Adam Schiff, the homeland security chair, Bennie Thompson, the oversight chair, Carolyn Maloney, and the judiciary chair, Jerrold Nadler. Officials have trained much of their focus on Sunday, when the anti-government “boogaloo” movement flagged plans to hold rallies in all 50 states. In Michigan, a fence was erected around the capitol in Lansing and troopers were mobilized. The legislature canceled meetings next week, citing credible threats. “We are prepared for the worst but we remain hopeful that those who choose to demonstrate at our Capitol do so peacefully,” the Michigan state police director, Joe Gasper, said. The perception that the 6 January insurrection was a success could embolden domestic extremists motivated by anti-government, racial and partisan grievances, spurring them to further violence, according to a government intelligence bulletin dated Wednesday first reported by Yahoo News. The Joint Intelligence Bulletin, produced by the FBI, Department of Homeland Security and National Counterterrorism Center, further warned that “false narratives” about electoral fraud would serve as an ongoing catalyst for extremists. Thousands of armed national guard troops were in the streets in Washington in an unprecedented show of force after the assault on the Capitol. Bridges into the city were to be closed along with dozens of roads. The National Mall and other landmarks were blocked off. Experts say the capitals of battleground states such as Wisconsin, Michigan, Pennsylvania and Arizona are at most risk of violence. But even states not seen as likely flashpoints are taking precautions. The Illinois governor, JB Pritzker, said on Friday that while his state had not received any specific threats he was beefing up security around the capitol in Springfield, including adding about 250 state national guard troops. The alarm extended beyond legislatures. The United Church of Christ, a Protestant denomination of more than 4,900 churches, warned its 800,000 members of reports “liberal” churches could be attacked. Suzanne Spaulding, a former undersecretary for the Department of Homeland Security, said disclosing enhanced security measures can be an effective deterrent. “One of the ways you can potentially de-escalate a problem is with a strong security posture,” said Spaulding, a senior adviser at the Center for Strategic and International Studies. “You try to deter people from trying anything.”