(CBS SF) — If you saw a Twitter conversation-turned-threat between your airline and a user with ISIS referenced in their name hours before your flight, would you reconsider your travel plans?

It’s a serious question passengers are likely contemplating as a disturbing trend of new threats targeted at airlines already prompted the evacuation of at least five flights over the last couple of days.

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The latest case comes Tuesday when a bomb threat was made against a Southwest Airlines flight scheduled to depart from San Diego Tuesday morning.

The threat, made via Twitter, was one of several made against various Southwest flights over the last several days, including an earlier one made against another flight out of San Diego on Monday.

Twitter has reportedly taken action against one of the threatening users, @ISISGangCP, by suspending their account about one hour after the user tweeted a bomb threat to Southwest and Delta Airlines Monday. The airlines responded immediately via Twitter.

Southwest or Delta have not confirmed if these are viable threats, only that they are taking them seriously.

The FBI is heading the investigation of these most recent threats, according to a spokesperson with the Transportation Security Administration, in addition to several other cases from over the weekend.

On Sunday, a Delta flight from Los Angeles to Orlando was diverted to Dallas after reports of a bomb threat made on Twitter. The same day, a JetBlue flight from Long Beach, Calif., and a SkyWest jet from Phoenix were evacuated amid security concerns.

Both incidents came the day after bomb threats targeted two jets bound for Atlanta, prompting F-16 fighter jets escorting  the planes. All planes landed safely with no injuries to passengers or flight staff reported.


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