A power bank exploded on a Royal Brunei Airlines flight going from Hong Kong to Brunei’s capital Bandar Seri Begawan last Thursday, with all passengers and crew members unharmed.

The explosion was made public by Facebook user Francis Ngu Hown Hua, who posted videos and images of the incident on his account, The Straits Times reported. The videos and images, showing a smoky cabin and passengers covering their faces, went viral.

Flight attendants calmly took care of what seemed to be a small fire caused by the power bank. The carrier later issued a statement on their website, describing the case as a “power bank incident.”

They also stated that their cabin crew members were trained to follow standard procedures in handling such situations to ensure the safety of passengers at all time. Hua praised the crew members for their composure and professionalism in taking care of the situation.

Royal Brunei Airlines Flight BI636 landed safely at Bandar Seri Begawan on January 3. The exact cause of the explosion has yet to be disclosed.