The FBI is spearheading an investigation into a suspicious substance found at the Baltimore district office of Rep. Elijah E. Cummings.

The Maryland Democrat released a statement this afternoon saying that when his staff arrived at his district office this morning, they discovered a “putty-like substance on the outside of the front door.”

“The Baltimore City Police were contacted and they sent a bomb technician to analyze the substance,” the release from Cummings said. “The police advised my staff not to enter the building. The bomb technician determined that the substance was not explosive material and that there was no active threat.”

Baltimore Fire Department spokesman Ian Brennan said the city’s hazardous materials team was called in about 11:30 a.m. and was at the office for “maybe an hour or so.”

Brennan also said the results of those tests would be announced by the FBI, which took over the lead on the investigation.

Cummings said the FBI was removing the substance and collecting evidence from the front door and surrounding area.

The Maryland Democrat is the ranking member of Oversight and Government Reform Committee.