Miami powder

Security workers evacuated a portion of Miami International Airport's A Concourse Wednesday night after a powdery substance was found aboard an American Airlines plane departing for Peru.

Police dogs did not indicate a threat from the powder, but a bomb squad was checking the area about 9 p.m. to be sure, Transportation Security Administration spokeswoman Sari Koshetz said.

''When there is a concern like this, our protocol is to evacuate a certain area and use an abundance of caution in evaluating the situation,'' Koshetz said.

American Flight 917 was scheduled to depart from Miami to Lima's Chavez International Airport at 5:30 p.m. It was parked at gate A10 at Miami International when the suspicious substance was discovered.

The plane and surrounding gate area were evacuated as investigators checked things out. The flight was rescheduled to depart at 8 a.m. Thursday, according to aviation website flightstats.com.