The Secret Service is expected to conclude its investigation into a bag of cocaine found in the West Wing early next week, a federal law enforcement official told CNN -- regardless of whether a suspect is identified.

As of Thursday afternoon, investigators had yet to receive results of the DNA or fingerprint analysis, but had already begun reviewing visitor logs and security camera footage.

This timeline reflects the current progress of the investigation, but law enforcement investigations are fluid and that timeline could shift.

The official reiterated that it may be difficult to identify a culprit given how many people walk through the entrance near where the bag of cocaine was found.

CNN previously reported that cocaine was found in a cubby near the ground floor entrance to the West Wing where staff-led tours of the White House pass through on their way into the building. Those tours typically only occur on weekends.

Visitors entering the West Wing for tours are asked to leave their phones in those cubbies, which can also be used by staff who cannot bring their phones into a SCIF, or sensitive compartmented information facility, where classified materials are handled.