Julie Hasquet, press secretary for U.S. Sen. Mark Begich, said the FBI determined the powder wasn't a threat and there was no criminal intent involved in the mailing, CNN reported Tuesday. U.S. Rep. Don Young said in a statement it was unclear why the material was sent, the Fairbanks News-Miner reported.
The man who mailed the packages told FBI investigators he sent samples of concrete material to each of the lawmakers, Hasquet said.
The packages were mailed to the Fairbanks offices of Begich and Sen. Lisa Murkowski, and Young's Anchorage office, police said.
A hazardous materials team was called to Young's office, CNN reported.
"It was one of those situations where we react according to a prescribed plan and we followed the plan," Anchorage Police Department Lt. Dave Parker said.