Climate activists glued themselves to the ground at Cologne-Bonn Airport in western Germany on Wednesday – forcing the suspension of flights, authorities said.
Police said five people glued themselves to a taxiway at the airport early in the morning, German news agency dpa reported.
Flights were suspended at about 5.45am. The protesters had been removed and flights were cleared to resume shortly after 9am.
The Last Generation activist group said in a statement that supporters in several small groups cut through the perimeter fence, approached the airport and then glued themselves to the asphalt with a mixture of sand and glue.
The group is demanding that the German government negotiates and sign an international agreement on a global exit from the use of oil, gas and coal by 2030.
It was the latest of several airport protests by climate activists in recent years that caused disruption to flights.
Last week, the German Cabinet approved legislation that would impose tougher penalties on people who break through airport perimeters.
The bill, which is still under consideration by lawmakers, foresees punishment ranging up to a two-year prison sentence for people who intentionally intrude on airside areas of airports such as taxiways or runways, endanger civil aviation, or enable someone else to.
So far, such intrusions can only draw a fine.
A sentence of up to five years would be possible in cases where someone forces their way into an airport with banned objects such as a weapon, certain knives, poisonous substances, or if the intrusion is intended to enable or cover up another offence.