Threatening note diverts Texas-bound commuter jet to Phoenix

A commuter flight carrying 42 passengers from San Francisco to San Antonio, Texas, was diverted to the Phoenix airport Thursday after a threatening note was found, authorities said.

Flight records showed that United Express Flight 5733, a Canadian-made Bombadier CRJ700 regional jet operated by SkyWest Airlines, landed at Phoenix Sky Harbor International Airport at 4:49 p.m. (6:49 p.m. ET). It had been scheduled to arrive in San Antonio at 9:24 p.m. ET.

A spokeswoman for United told NBC News that all passengers were safely off the plane, which was swept after a threatening note was found. Nothing else was found, officials said.

The FBI told NBC News it wouldn't disclose the specific nature of the threat.

Other flights at the Phoenix airport weren't affected, and no delays were reported, the Federal Aviation Administration said.

Andrew Blankstein of NBC News contributed to this report.

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