A Swiss International Air Lines plane arrived at its destination without a single checked bag onboard.

The plane arrived in Bilbao, Spain, on Saturday without any of the passengers’ checked bags. The bags were left behind in Zurich, Switzerland, Kavin Ampalam, a spokesperson for Swiss, told the news agency AFP.

Passengers waited in vain for more than two hours at a conveyor belt for their suitcases, according to the Swiss-German newspaper The Blick.

“There was a shortage of ground staff,” Ampalam told AFP. Ampalam said the flight departed without its 111 passengers’ suitcases “for operational reasons,” as the plane had to fly another set of passengers from Bilbao to Zurich Airport before it closed. Swiss was operating the flight on behalf of Edelweiss Air, Ampalam said.

Ampalam said the flight crew waited for “one hour and 16 minutes” for the ground staff to load the bags onto the plane before deciding to fly to Bilbao without them.

“We understand the situation is not favourable for the people involved, and of course we regret the inconvenience,” Ampalam told AFP.

Several passengers said the pilot in charge of the flight was apologetic over the delayed departure, but never mentioned leaving their bags in Zurich, according to Blick’s report.