A former United States army soldier who was convicted of manslaughter for shooting a handcuffed civilian in Iraq to death was arrested on Monday on charges that he assaulted police officers with a baton during the US Capitol attack. Edward Richmond Jr, 40, of Geismar, Louisiana, was wearing a helmet, shoulder pads, goggles and a Louisiana state flag patch on his chest when he attacked police in a tunnel outside the Capitol on January 6, according to an FBI agent’s affidavit. Richmond was arrested in Baton Rouge, Louisiana, and was scheduled to make his initial court appearance on Tuesday on charges including civil disorder and assaulting, resisting or impeding police with a dangerous weapon. Richmond’s Louisiana-based attorney, John McLindon, said he had not seen the charging documents and therefore could not immediately comment on the case. Aged 20, Richmond faced a court-martial panel which convicted him of voluntary manslaughter and sentenced him to three years in prison for killing a handcuffed Iraqi civilian near Taal Al Jai in February 2004. Richmond also received a dishonorable discharge from the army. Richmond initially was charged with unpremeditated murder, which carries a maximum sentence of life in prison. But the panel of five officers and five enlisted soldiers reduced the charge to voluntary manslaughter. The army said Richmond shot Muhamad Husain Kadir, a cow herder, in the back of the head from about 6ft away after the man stumbled. Richmond testified that he didn’t know Kadir was handcuffed and believed the Iraqi man was going to harm a fellow soldier. During the January 6 riot, body camera footage captured Richmond repeatedly assaulting police officers with a black baton in a tunnel on the Capitol’s lower west terrace, the FBI said. Police struggled for hours to stop the mob of people supporting Donald Trump from entering the Capitol through the same tunnel entrance. A witness helped the FBI identify Richmond as somebody who had traveled to Washington DC with several other people to serve as a “security team” for the witness for rallies planned for January 6, according to the agent’s affidavit. More than 1,200 people have been charged with Capitol riot-related crimes. About 900 have pleaded guilty or been convicted after trials. More than 750 have been sentenced, with nearly 500 receiving a term of imprisonment, according to data compiled by the Associated Press.