WASHINGTON, Jan 20 (Reuters) - A judge on Thursday refused to release from jail a member of the far-right Oath Keepers group charged with seditious conspiracy over allegations he helped plan the deadly Jan. 6, 2021, attack on the U.S. Capitol. Edward Vallejo, one of 11 people prosecutors have linked to the Oath Keepers and accused of seditious conspiracy, lost an attempt to be released from jail while he awaits trial. "You are a serious danger at this time," U.S. Magistrate Judge John Boyle in Phoenix, Arizona, said during a court hearing and ruled pretrial detention was necessary for Vallejo, 63. In a Jan. 18 court filing, the Justice Department said Vallejo was a co-conspirator in a plot orchestrated by Oath Keepers leader Stewart Rhodes to attack Congress and forcefully oppose the transfer of power between then-President Donald Trump, a Republican, to his successor, Biden, a Democrat. The riot was fueled by Trump"s false claims that his November 2020 election defeat was the result of fraud. "Vallejo played a central role in the planned use of force in this plot, agreeing and preparing to usher firearms and other related equipment into Washington, D.C., to his co-conspirators," the Justice Department said in the court filing. The judge said the evidence suggests Vallejo would have ushered the firearms into the District of Columbia if Rhodes had given such an order. "I think if Mr. Rhodes had given that order, you would have complied," Boyle said in court on Thursday. Prosecutors said that Vallejo "also poses a risk of obstruction of justice should he be released." Vallejo"s lawyer said at the court hearing that he would plead not guilty to all charges. An indictment released on Jan. 13 against the 11 was the first time suspected participants in the attack were charged with seditious conspiracy, which is defined as attempting "to overthrow, put down or to destroy by force the government of the United States."