Police in Germany's northern city of Hamburg on Friday said they stopped climate activists from disrupting operations at Hamburg airport.

A police crew stopped a group of cyclists near the airport at around 5 a.m. local time (0300 UTC/GMT).

The officers found equipment in the suspects' bags that "suggested an intended blockade action at the airport," the police said.

The equipment included bolt cutters, vests, posters and a sand-resin mixture.

Four suspects were temporarily detained but several others in the group reportedly fled the scene.

A fifth suspect, who police think planned to video the blockade from a vantage point in the airport, was also arrested.

Police said several officers were deployed to guard the fence to the runway, while a helicopter was used to monitor the scene and track down the suspects.

A spokesperson for Hamburg Airport said the police operation had no impact on flights departing or arriving.

Protests at several German airports 

After a six-month lull, climate protests resumed in July at several German airports, including Munich and Dusseldorf.

Early on Thursday, a group of protesters glued themselves to the runway at Leipzig/Halle Airport, which delayed cargo flight operations.

On July 25, demonstrators targeted Frankfurt and Cologne-Bonn airports with similar disruption, which grounded flights for a few hours.

A peaceful protest was also held at Stuttgart Airport on the same day.

The German climate group Last Generation explained their rationale for the controversial action on X, formerly Twitter, Thursday. They said the airport protests were arranged to "call for the signing of an international fossil fuel phase-out agreement."

Other climate groups have staged similar protests at other airports around Europe, including in Norway, Switzerland and Finland, where a group of activists blockaded the security gates at Helsinki airport.

Berlin cracks down on controversial stunts

Last month, the German government approved legislation that would impose tougher penalties on those who break through airport perimeters.

Several airports have stepped up security to prevent further disruption.

The provocative protests have received criticism and praise for highlighting the urgent need to phase out fossil fuels to tackle climate change.

But some climate protesters have blocked bridges and motorways, and even thrown liquids on protective glass over classic paintings and monuments, drawing ire from politicians and the public alike.

mm/ab (dpa, DW sources)