U.S. Attorney for D.C. Jeanine Pirro said she has “no doubt” that Cole Tomas Allen, the suspect in the shooting at the White House Correspondents’ Association Dinner, fired a shotgun at a Secret Service agent, who was wearing a protective vest.

“The grand jury agreed that there was probable cause to believe that it was Cole Allen’s weapon that hit the Secret Service agent,” she told ABC News’ Chief Justice Correspondent Pierre Thomas on Tuesday, the same day a grand jury returned a four-count indictment against Allen.

Three of the charges against Allen had already been charged by criminal complaint, including attempting to assassinate the president, transportation of a firearm with intent to commit a felony and discharge of a firearm during a crime of violence. The fourth new charge is assaulting a federal officer with a deadly weapon, according to the indictment.

The California native was tackled by law enforcement after the gunfire April 25 inside the Washington, D.C., Hilton hotel, where thousands of journalists, as well as President Donald Trump and members of his Cabinet, were gathered for the annual dinner.

Allen did not reach the ballroom, where the dinner was underway. The Secret Service member was shot during the incident, but the bullet hit the agent’s protective vest, officials said.

Pirro’s comments go beyond what prosecutors have disclosed publicly so far of ballistics evidence against Allen.

In a court filing last week, Allen’s attorneys questioned what evidence the government has to determine he fired his weapon. They have not spoken publicly about the case other than through court filings.

Prosecutors have yet to release evidence that shows the results of ballistics tests on the shotgun or what struck the Secret Service agent.

In the interview with ABC News on Tuesday, Pirro discussed more details of what she said the ballistics evidence reveals.

“One of the pellets — part of the buckshot had fibers that are consistent with having come from the Secret Service officer;s vest,” she said. 

Prosecutors have said in documents that Allen fired the shotgun at least once as he ran past the magnetometers, and they said he fired “in the direction” of the Secret Service officer who was struck in the vest. Prosecutors said one spent cartridge case was recovered from the chamber and “at least one fragment was recovered from the crime scene that was physically consistent with a single buckshot pellet.”

Allen — who officials say traveled by train from California to D.C. — allegedly left a note which said that administration officials were his targets.

The suspect allegedly wrote that Secret Service agents were targets “only if necessary, and to be incapacitated non-lethally if possible,” the complaint said.

Allen has not yet entered a plea.

Following the shooting, Trump vowed that the annual dinner for White House journalists would be rescheduled within 30 days.

“I’m looking forward to this being rescheduled, as the president is hoping, in the next 30 days, because this is a tremendous opportunity for all sides to come together, and I’m excited about that,” Pirro said.

However, she said remains concerned about the potential for violence in D.C. amid a series of recent incidents involving armed suspects allegedly traveling across state lines to carry out violent acts in the nation’s capital.

“All I can tell you is that we are ready and we are very concerned about this happening again. I’m doing everything in my power to protect the people of the District, the people who live here, the people who work here, and the people who visit,” she said.