Several gates inside a terminal at Washington Dulles International Airport were evacuated Saturday after a bomb-sniffing dog alerted to cargo that was being loaded onto an aircraft, a Transportation Security Administration spokesman said.

The gates were evacuated out of an abundance of caution, TSA’s Greg Soule said.

An ordnance team from Virginia State Police was on the scene.

The partial evacuation began about 4:30 p.m. ET. Only two flights were affected by the incident and arriving flights were being sent to alternate gates, airport spokesman Rob Yingling said.

CNN’s Mike M. Ahlers and Carol Cratty contributed to this report.