BONN — Climate activists have glued themselves to the runway at Cologne-Bonn Airport, one of Germany's biggest airports.

Flights were stopped but they have now resumed, with the airport saying: "The police operation at Cologne/Bonn Airport is over. Flight operations have resumed. Disruptions in the form of delays and flight cancellations are to be expected during the course of the day."

Police said five people glued themselves to a taxiway at the airport early this morning and officers were trying to dislodge them, German news agency DPA reported. By 8.30 am, two of them had been removed.

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.

Acting under the banner 'Oil Kills' the protesters say: "We are demanding our criminal governments phase out oil, gas and coal by 2030 by signing a binding international treaty.

Through coordinated actions around Europe, they ask, "our governments..to stop extracting and burning oil, gas and coal by 2030 as well as supporting and financing poorer countries to make a fast, fair, and just transition."

In Finland, activists were photographed obstructing the security gates at Helsinki Vantaa Airport.

In Norway, three activists reportedly breached the perimeter fence of Oslo’s Gardermoen Airport. Norwegian media reported that these individuals were removed by authorities within 30 minutes of gaining access.

These are 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, or poisonous substances, or if the intrusion is intended to enable or cover up another offense. — Euronews