ERKELENZ (dpa-AFX) - On the outskirts of the operation in the lignite town of Lützerath, a civilian police emergency vehicle burst into flames. "We definitely assume arson," said a police spokesman on Thursday. The civilian emergency vehicle had stood near the protest camp in the neighboring village of Keyenberg and was clearly recognizable as a police car by a blue light on the roof. It is assumed that the perpetrators broke the window and poured a flammable liquid into the car. It was initially unclear whether any suspects could be identified./mhe/DP/men