(WASHINGTON) — The U.S. Secret Service on Thursday will give a classified briefing to members and staff of the Republican-led House Oversight Committee on the cocaine found in the White House West Wing earlier this month, a spokesman for the agency confirmed to ABC News.

Committee chair James Comer, R-Ky., said the discovery raises questions about security at the White House when he requested the briefing in a letter sent to Secret Service Director Kimberly Cheatle on July 7.

“This alarming development requires the Committee to assess White House security practices and determine whose failures led to an evacuation of the building and finding of the illegal substance,” Comer wrote.

The briefing will take place behind in a SCIF — a sensitive compartmented information facility used to handled classified information — and will start at 10 a.m. ET, according to a source familiar with the situation.

The Secret Service has been investigating since the drug was found at the White House complex on July 2. So far, no one has been blamed for bringing in the illegal substance.

The White House was briefly shut down and the D.C. Fire Department was called to the scene when a powdery, cocaine-like substance was found inside a work area. Testing later confirmed the substance was cocaine.

A source familiar with the matter told ABC News the drug was located inside a cubby near the West Executive entrance where visitors typically drop off their cellphones and other belongings.

As part of the probe, the Secret Service was reviewing the security footage and visitor logs.

White House press secretary Karine Jean-Pierre said there had been tours conducted the Sunday the substance was found as well as the two days prior, and described the area as “highly traveled.”

President Joe Biden, first lady Jill Biden and other Biden family members left Friday afternoon to spend the weekend at Camp David.

The White House has declined to extensively comment on the incident. Jean-Pierre was peppered with questions during a press briefing last week, but only told reporters that Biden had been briefed on the matter and the White House was confident the Secret Service would “get to the bottom of this.”

“We are not involved in this,” Jean-Pierre said. “This is something that the Secret Service handles. It’s under their protocol.”

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