According to sources, a letter sent to Alabama Attorney General Luther Strange earlier this week — the letter that contained a suspicious, white, powdery substance and led to the evacuation and lockdown of the state office — originated from an inmate at the Dallas County Jail.

As for the white substance, it has proven to be dried toothpaste, used to reseal the previously used envelope.

“State investigators were here Wednesday and interviewed the inmate,” Dallas County Sheriff’s Department Chief Deputy Randy Pugh confirmed Friday. “We cooperated with them fully and while they were here, they discovered that the powdery substance was toothpaste the inmate used to reseal the envelope.”

Pugh did not release the name of the inmate or details of the letter, saying only the letter was a complaint letter sent to Strange’s office.

Anna Morris, a spokesperson with the Alabama Law Enforcement Agency, and Robyn Litchfield, a spokesperson with the Alabama Department of Public Safety, declined to comment on the Dallas County connection, both saying they could not comment on what they called “an ongoing investigation” by the Alabama Bureau of Investigation.

Wednesday, a letter was received by the Alabama Attorney General’s Office in Montgomery. Officials said a secretary in the office opened the letter and discovered the white substance.

The office was evacuated and quarantined while initial testing was performed by the United States Postal Service. The initial tests showed the substance to be harmless.

The substance was then removed from the building and further tests were performed by the Alabama National Guard Civil Support Team confirming the substance was not hazardous.

Morris said the offices remained closed for “several hours” Wednesday.

While the end result proved to be harmless, Pugh said he understood the quick action of state officials, responding to the situation as if the material were anthrax or another harmful agent.

“I’m impressed by how fast they responded, how seriously they took everything,” Pugh said. “They have to be careful and treat everything as if it’s the worst possible case.”

Neither Pugh nor state officials would speculate if any charges would stem from the scare, each saying it would depend on the results of ABI’s investigation.