Aviation watchdog to probe plane toke incident

China's aviation regulators are continuing investigations into a case where crews on a China United Airlines (CUA) flight allegedly allowed passengers to smoke on the plane.

"We will carefully examine how they handled the incident," the North China management bureau of Civil Aviation Administration of China (CAAC) said in a statement.

The CAAC statement came three days after passengers onboard domestic flight KN5216 from Chengdu to Beijing complained of passengers smoking mid-flight and that flight crews failed to rerun security checks despite passenger requests.

According to accounts by passengers, an individual was caught smoking inside the toilet during the flight. The match used to light the cigarette was later confiscated by cabin crew, but fire alarms were not set off.

Upon arrival at a stopover in Taiyuan airport, several passengers lit up cigarettes in the gate area, where smoking is forbidden, before boarding for the next leg of the trip.

Other passengers demanded a second security check, but the captain refused, passengers said.

No one was detained or injured during the incident.

How and where the smoking passengers got their matches remains unknown.

In a statement on Monday, CUA apologized for the inconvenience caused during the incident, but insisted the smoking was "dealt with immediately by the crew."

"Further investigation is still under way and staff who violated regulations will be dealt with seriously," the CUA statement said.

Once on the ground, dozens of passengers mobbed the flight crew, protesting the handling of the incident.

According to Chinese laws, lighters and matches are banned from planes.