According to a volunteer at the White House Correspondents’ Dinner, the alleged shooter was seen assembling a “long” firearm in a minimally supervised area near the entrance on the terrace level before firing shots and advancing toward the ballroom.

The eyewitness, Helen Mabus, who volunteered at the event and hails from Harrisburg, Pennsylvania, described the location as a “makeshift room” near the entrance, used for storing bar carts, where security presence was notably absent at that moment.

“He was in that room,” Mabus recounted, mentioning that the individual retrieved the item from a bag. She noted that the weapon appeared “long” and didn’t resemble a “typical gun.”

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Mabus observed that the suspect was partially hidden from security view while handling the weapon inside the room, before abruptly making his way toward the main event area.

“He assembled it and then rushed towards the stairs leading down to the ballroom,” Mabus explained.

The gunman then began firing in multiple directions as guests and staff scrambled to escape.

“It just seem like he was shooting all over the place,” Mabus said, estimating she heard “at least 10 shots.”

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She said the gunfire triggered immediate panic, with people “screaming and running” while Secret Service and other armed personnel rushed toward the danger.

Mabus said she fled in the opposite direction and did not see the suspect apprehended, adding that the chaos unfolded just steps from the path leading down to the ballroom where hundreds of high-profile guests had gathered.

This is a developing story. Please check back for updates.