The European head of U.S. auto giant General Motors said the company could close the Opel car plant in Bochum as stoppages continued at the factory Saturday. Fritz Henderson said in an interview with Sunday's Welt am Sonntag newspaper a plant closure could not be ruled out. The Bochum works was in the worst position of all Opel's plants in Germany which are under the threat of massive job cuts, he said. Workers at the Bochum plant stopped production for a second straight day in protest at plans by the U.S. parent company to slash some 4,000 jobs. Workers protested with their wives and children outside the plant and said the protests would continue Sunday. Works council officials said the workers were not on strike but gathering for an "information meeting". Opel workers are pressing for similar stoppages at the company's plants in Belgium, Poland and Britain. Europe-wide protests are planned at Opel factories on Tuesday. General Motors wants to cut 12,000 jobs at its loss-making car factories in Europe. Some 10,000 of the cuts are earmarked for Germany, about a third of the 32,000-strong German workforce. The German government has ruled out any bail-out, but Economy Minister Wolfgang Clement has urged the company to achieve cutbacks without compulsory redundancies.