DANNENBERG, Germany (Reuters) - German police used truncheons and teargas Sunday to clear rail lines as they clashed with anti-nuclear activists trying to disrupt a shipment of nuclear waste heading to a storage dump.

Thousands of demonstrators engaged some 17,000 police in running battles all day long Sunday and forced the delay of the shipment of 154 metric tons of nuclear waste by more than 10 hours, police said.

Some 3,000 activists were sitting on the tracks outside Dannenberg Sunday evening, further delaying the convoy. The nuclear waste was not expected to reach its destination, a nuclear dump in Gorleben, until Monday.

“We’re expecting further violence,” police spokesman Aachim von Remmenden told ZDF television. “It’s unfortunate considering that most of the protesters were peaceful.”

Violence erupted early Sunday when 250 activists tried to damage the track near the waste dump to halt the train. When police tried to stop them, the activists responded using flare guns and a chemical spray that caused eyes to tear up.

Riot police used truncheons, teargas and water cannon to stop the violent activists, who were part of a larger group of about 4,000 protesters near the town of Leitstade trying to halt the train.

A small fire was started under an armored police vehicle and it was seen smouldering in images broadcast on German television. Police said activists had poured tar on it and thrown small petrol bombs at and under the vehicle.

PUBLIC OPPOSITION

Police repeatedly tried to stop activists from removing gravel under the rail tracks. Some police were pushed and shoved from behind as they tried to carry activists away.

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The helmet-clad police also were seen in broadcast images punching activists and hitting them with truncheons as small fires burned on the tracks and in the surrounding forests.

“Those who resort to violence against police officials have to expect us to respond accordingly,” a police spokeswoman told N-TV television, saying there had been “massive acts of violence against police” Sunday.

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About a dozen protesters were injured, demonstrators were quoted as saying in local media reports.

The waste shipment has become a tense political issue due to anger over Chancellor Angela Merkel’s decision to extend the lifespan of Germany’s 17 nuclear power plants despite overwhelming public opposition.

The waste originated in Germany and was reprocessed at the French nuclear group Areva’s processing plant at La Hague for storage in a site in the northern German town of Gorleben.

The train was held up repeatedly on its way across France and Germany on a journey that began Friday. In Germany thousands staged sit-down strikes on tracks and others lowered themselves on ropes from bridges to prevent the train from passing. They were removed by police.

Merkel’s government has slumped in popularity due largely to its decision to extend nuclear power by about 12 years beyond the original shutdown set for 2021. Germany gets 23 percent of its power from nuclear plants.

Scenes of violence during previous shipments have contributed to Germany’s strong anti-nuclear mood.

Protesters fear the depot at Gorleben, built as an interim storage site, could become permanent. Greenpeace says the site, in a disused salt mine, would be unsafe over the long term.