A grandmother was catching up with a close friend in January when the woman shared some news about her son in New Jersey.

Robert Lee Petrosh, the woman told her friend, had stormed the Capitol building during the Jan. 6 insurrection.

The grandmother did not keep that news to herself. She told her grandson, who days later, court records show, called the FBI to report Petrosh.

Now Petrosh, who lives in Mays Landing, N.J., faces multiple federal charges over his alleged role in the deadly riot, according to a criminal complaint unsealed on Wednesday.

Neither Petrosh, 51, nor his attorney immediately responded to messages from The Washington Post late Wednesday.

The New Jersey man is among hundreds now charged in connection with the Jan. 6 insurrection, including many who were turned in by relatives, friends and co-workers who learned of their participation by word of mouth or their social media posts, as The Post’s Hannah Knowles and Paulina Villegas have reported.

Last month, prosecutors charged a New York man who allegedly boasted about his role in the riots to a woman on a dating app. On Tuesday, a Pennsylvania man was charged after his wife’s Facebook posts allegedly placed him at the Capitol that day.

Many have argued that President Donald Trump's efforts amounted to an attempted coup on Jan. 6. Was it? And why does that matter? (Monica Rodman, Sarah Hashemi/The Washington Post)

Even before the grandmother’s conversation sparked a new tip, the FBI had been alerted about Petrosh’s alleged role in the riots, court records show. On Jan. 10, an anonymous online tipster said Petrosh “was on the steps” of the federal building on Jan. 6.

A week later, on Jan. 17, court records show, the woman’s grandson called the FBI to report on Petrosh, whom he described as a White man in his 40s or 50s with a round face, red cheeks and short hair. He later identified Petrosh in photos obtained by the agency and said Petrosh “had been lying low following the arrests of other individuals who entered the U.S. Capitol building.”

Later that month, an FBI task force officer who said he has known Petrosh for about 15 years identified him in two photos from inside the Capitol. In one photo included in the criminal complaint, Petrosh, who is wearing blue jeans and a black long-sleeved T-shirt, sits on a bench inside the Capitol. The second photo shows Petrosh, in the same outfit, standing near the door to the House Wing at about 3:20 p.m.

The FBI task force officer later told the agency that he previously worked with Petrosh and attended social gatherings with him and said he had occasionally seen Petrosh working in his yard or garden.

Petrosh, who turned himself in earlier this week, is charged with knowingly and unlawfully entering or remaining in a restricted building, disorderly conduct in a Capitol building and other counts. He was released on a $50,000 bond and is due back in court on Tuesday, court records show.