WASHINGTON -- The Secret Service on Thursday said its investigation into how cocaine ended up at the White House is now closed without identifying a suspect.
The agency statement came after congressional Republicans said they were told in a classified Secret Service briefing that the investigation into the cocaine found in the White House West Wing earlier this month was concluding without a determination of who was responsible.
"There was no surveillance video footage found that provided investigative leads or any other means for investigators to identify who may have deposited the found substance in this area," the agency said in a lengthy statement. "Without physical evidence, the investigation will not be able to single out a person of interest from the hundreds of individuals who passed through the vestibule where the cocaine was discovered. At this time, the Secret Service's investigation is closed due to a lack of physical evidence."
The Secret Service said the packaging was "subjected to advanced fingerprint and DNA analysis," by the FBI crime lab.
"The investigation included a methodical review of security systems and protocols," the agency statement said. "This review included a backwards examination that spanned several days prior to the discovery of the substance and developed an index of several hundred individuals who may have accessed the area where the substance was found. The focal point of these actions developed a pool of known persons for comparison of forensic evidence gleaned from the FBI's analysis of the substance's packaging.
"On July 12, the Secret Service received the FBI's laboratory results, which did not develop latent fingerprints and insufficient DNA was present for investigative comparisons," the statement said.
Following Thursday's closed-door briefing to members and staff of the House Oversight Committee, Republicans said they viewed the development as a "failure" of the agency and said the briefers said the investigation was concluding.
"And to say that they don't know who it is, to me, somebody should lose their job over this. This thing's a trash can. Everybody wants to pick and choose they need to shut the whole thing down put the garden hose to it and clean it out," Rep. Tim Burchett said, adding that the Secret Service told members in the briefing the bag contained less than a gram of cocaine.
Members told reporters the Secret Service informed them they narrowed down the list of suspects to 500 people during the weekend that cocaine was found and said that group included a mix of staffers and visitors who were on a tour. West Wing tours are invitation only.
Members said they were told there are 182 lockers on the wall where visitors are typically told to store their electronics and cell phones. They said they were told the cocaine was found in locker 50.
GOP Rep. Lauren Boebert said the key to that locker is missing.
"There's no collateral system in place. There's no assigning of the lockers. And this was one of the concerns I raised to Secret Service. We need to be able to track individuals and which locker they are using," she said.
CNN first reported the Secret Service's conclusion.
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 took place behind closed doors in a SCIF -- a sensitive compartmented information facility used to handled classified information.
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 cell phones 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 the White House 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."
ABC News' Laren Peller, Will Steakin and Molly Nagle contributed to this report.