Passengers at Munich airport after 130 flights were cancelled. PETER KNEFFEL / GETTY

Some mistakes may seem innocuous yet they can carry a high price. A young man from Spain on Tuesday involuntarily triggered a security alert at Munich airport after walking through the wrong door on his way to catch a Madrid flight, said federal police in Germany.

As a result 130 flights were cancelled, causing numerous delays at one of the country’s busiest airports, which was partially shut down for four hours. The Spaniard could face criminal proceedings over the incident.

The man said he was “horrified” at the outcome of his mistake

The man, who is reported to be aged between 20 and 25 years old, was on his way home after spending his vacation in Thailand and has stated that he was “horrified” at the outcome of his mistake during a stopover in Munich.

The Spaniard was arrested and interrogated by German security forces soon after the incident, which took place on Tuesday morning. He said that he had gone to the bathroom after stepping off a flight from Bangkok, and by the time he left the men’s room all the other passengers had gone. Disoriented, he began walking in the wrong direction as he tried to find his connecting flight to Madrid.

He eventually pressed a button opening emergency doors to the restricted area reserved for passengers who have gone through a security check, according to the Bavarian public station BR24 and the local newspaper Merkur. This immediately triggered an alert, as it meant that a passenger from outside the border-free Schengen Area had bypassed passport controls. Parts of Terminal 1 and 2 were evacuated, and passengers who had already gone through security checks had to repeat the process.

There were around 1,200 departures scheduled at Munich airport on Tuesday, representing a flow of around 120,000 passengers.