Earlier this week, a United Airlines flight had to be diverted after several passengers became frightened and angry when they were seated next to a passenger they believed to be sick with coronavirus.

According to  AP, Sunday, a flight headed to Newark, N.J., from Colorado made an unexpected stop in Denver shortly after takeoff. Authorities say the unscheduled detour was necessary because three frightened passengers became agitated and refused to follow crew members’ instructions.

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Denver police were waiting for the aircraft when it landed and escorted the unruly passengers away. But United has now confirmed that the disruption was triggered by the presence of a “sickly” passenger.

The passenger who suffers from allergies was coughing and sneezing. To address health concerns, she was screened for a fever on board and then allowed to continue her trip after the screening came back negative, station NBC Chicago reported.

A global pandemic

This weekend’s incident highlights growing hysteria over the spread of the novel coronavirus. The World Health Organization declared Wednesday that the global coronavirus crisis is now a pandemic.

Tedros Adhanom Ghebreyesus, who heads the U.N. agency, said the WHO is “deeply concerned by the alarming levels of spread and severity” of the outbreak. He also expressed concern about “the alarming levels of inaction.”

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“We have, therefore, made the assessment that COVID-19 can be characterized as a pandemic,” he said at a briefing in Geneva.

“All countries can still change the course of this pandemic. If countries detect, test, treat, isolate, trace and mobilize their people in the response,” Tedros said.