WASHINGTON - A federal jury convicted a former Rocky Mount, Va., police officer of storming the U.S. Capitol with another off-duty officer to obstruct Congress from certifying President Biden’s 2020 electoral victory.

Jurors on Monday convicted former Rocky Mount police officer Thomas “T.J.” Robertson of all six counts he faced stemming from the Jan. 6, 2021, riot and insurrection, including charges that he interfered with police officers at the Capitol and that he entered a restricted area with a dangerous weapon, a large wooden stick.

His sentencing hearing wasn’t immediately scheduled.

Mr. Robertson’s jury trial was the second among hundreds of Capitol riot cases. The first ended last month with jurors convicting a Texas man, Guy Reffitt, of all five counts in his indictment.

Mr. Robertson didn’t testify at his trial, which started April 5. Jurors deliberated for several hours over two days before reaching their unanimous verdict.

One juror, who spoke to The Associated Press only on condition of anonymity, said as she left the courthouse, “I think the government made a really compelling case and the evidence was fairly overwhelming.”

Defense attorney Mark Rol- lins said Mr. Robertson will appeal the jury’s verdict. “While Mr. Robertson disagrees with the jury’s decision, he respects the rule of law,” Mr. Rollins said in a statement.

A key witness for prosecutors in his case was Jacob Fracker, who also served on the Rocky Mount police force and viewed Mr. Robertson as a mentor and father figure. Mr. Fracker was scheduled to be tried alongside Mr. Robertson before he pleaded guilty last month to a conspiracy charge and agreed to cooperate with authorities. Mr. Fracker testified on April 7 that he had hoped the mob that attacked the Capitol could overturn the results of the 2020 presidential election.

Mr. Robertson was charged with six counts—obstruction of Congress, interfering with officers during a civil disorder, entering a restricted area while carrying a dangerous weapon, disorderly or disruptive conduct in a restricted area while carrying a dangerous weapon, disorderly or disruptive conduct inside the Capitol building, and obstruction. The last charge stems from his al- leged post-riot destruction of cellphones belonging to him and Mr. Fracker.

During the trial’s closing arguments last Friday, Assistant U.S. Attorney Risa Berkower said Mr. Robertson went to Washington and joined a “violent vigilante mob” because he believed the election was stolen from then-President Trump. He used the wooden stick to interfere with outnumbered police before he joined the crowd pouring into the Capitol, she said.

“The defendant did all this because he wanted to overturn the election,” Ms. Berkower said.

Mr. Rollins conceded that Mr. Robertson broke the law when he entered the Capitol during the riot. He encouraged jurors to convict Mr. Robertson of misdemeanor offenses but urged them to acquit Mr. Robertson of felony charges that he used the stick as a dangerous weapon and that he intended to stop Congress from certifying the Electoral College vote.

“There were no plans to go down there and say, ‘I’m going to stop Congress from doing this vote,’” Mr. Rollins said.

Mr. Fracker testified that he initially believed that he was merely trespassing when he entered the Capitol building. However, he ultimately pleaded guilty to conspiring with Mr. Robertson to obstruct Congress.

The town fired Mr. Robertson and Mr. Fracker after the riot. Rocky Mount is about 25 miles south of Roanoke and has roughly 5,000 residents.

Mr. Robertson has been jailed since U.S. District Judge Christopher Cooper ruled in July that he violated the terms of his pretrial release by possessing firearms.

More than 770 people have been charged with federal crimes related to the riot. More than 250 of them have pleaded guilty, mostly to misdemeanors.