Panic has gripped passengers aboard a Virgin flight as the aircraft plunged into an urgent descent, with no clear explanation from the crew until after landing.

The routine Sydney-to-Brisbane flight had departed just after 8.30pm on Wednesday, but around 9.10pm the cabin lost pressure, triggering an emergency response, a source told The Nightly.

According to a passenger, oxygen masks dropped from the ceiling as the plane completed a “sudden descent”, leaving those on board fearing the worst without updates from the crew.

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“Once we landed, we were told the cabin had lost pressure but no comms in flight,” the passenger said.

“It would have been great to know the plane was intact before 10 when we finally landed!”

The aircraft was able to conduct a normal landing in Brisbane, and there are no reports of injury to passengers or crew.

Virgin Australia confirmed the flight experienced a depressurisation event.

“We can confirm that VA933 Sydney to Brisbane arrived safely at Brisbane Airport after experiencing a depressurisation event on Wednesday, 13 August,” a spokesperson said in a statement.

“The flight crew took the appropriate steps, following standard operating procedures, to descend to a lower altitude. As part of that process, a PAN call was transmitted to Air Traffic Control.”

A PAN call is an international urgency signal used in aviation communication to indicate a situation that is urgent, but not an immediate threat to life or the aircraft itself, unlike a “mayday” distress call.

While Virgin did not respond to questions around what passengers were told on board, the airline insists they are committed to the well-being of guests and crew, and admit this may have been a distressing incident.

“Safety remains Virgin Australia’s number one priority, and we are reviewing the situation in line with our safety standards.”

The aircraft is currently being assessed by engineers.