The vice president's spokeswoman said Pence never left the Washington area and that the event will be rescheduled.
"A senior administration official reiterates there should be no cause for alarm. He looks forward to rescheduling the trip to New Hampshire very soon", Alyssa Farah, the vice president's press secretary, tweeted at 11:58 a.m. Tuesday.
In a statement, Granite Recovery Centers CEO Eric Spofford said, "We were so honored to host Vice President Pence to discuss the opioid epidemic, treatment, and recovery but unfortunately the event was canceled".
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King added that she was "just told it is not an "emergency" (1st word used) that the [vice president] is sent back to DC".
The White House did not return requests for comment.
Pence's plane never took off and he returned to the White House to meet with Trump.
Spokespeople for the VP and the White House said that there had been "no emergency callback" and that there was "no cause for concern." .
Reports are saying the Pease shooter scare has nothing to do with Pence's travel plans.
"So thankful everyone on our plane is safe", Pence said on Twitter after the incident. It was about to land and they had to call them back to Washington.