The incident happened at about 10:30 Tuesday morning. Staff members for Republican Joel Dykstra were opening mail in his U.S. senate campaign office when they came across an angry sounding letter with white powder.

"The message on the letter was very threatening. Very direct," said Dykstra.

Dykstra was at DakotaFest in Mitchell but his staff called 911. Soon Hazmat crews were suiting up outside the strip mall on Minnesota Avenue to find out what the white powder was. A special machine indicated it was baby powder, but crews didn't take any chances. Becky Otten's business is right next door to Dykstra's campaign office.

"The firemen did come in to let me know what was going on. We share the same heating and air conditioning system and stuff to make sure I was safe," said Otten.

Becky was safe as was everyone else in the building. Dykstra says if there's any silver lining, it's that law enforcement and rescue crews knew how to handle the situation. Dykstra says as for his campaign, it's back to business.

"We intend to carry on with activities of our campaign that we have been. And I believe we'll do that without too much further interruption," said Dykstra.

Even though that powder is believed to be baby powder, it's being sent to SDSU for further testing.