HOUSTON - A Delta flight was delayed at Bush Intercontinental Airport on Tuesday morning after a "non-specified" threat was made against several locations by telephone.

Several bomb-detecting K-9 units were called in to look over the aircraft, which was preparing to depart before it returned to the gate for a security sweep. Passengers and luggage were taken off of the plane so they could be re-screened.

The call came in at about 7 a.m., according to Bill Begley with the Houston Airport System. That flight, Delta 227, landed safely at its destination in Atlanta.

No other flights were impacted.