Prosecutors in Germany said Friday they had opened a formal inquiry into allegations that Finnish mobile phone manufacturer Nokia breached promises it gave in exchange for state aid, according to dpa. The maker of four in 10 phones sold worldwide, Nokia has triggered a political storm in Germany by announcing last month the closure of a 2,300-employee factory at Bochum, an unemployment black spot, so it can take advantage of cheaper labour in Cluj, Romania. Bernd Bieniossek, a Bochum prosecutor, said the official inquiry, the second stage of an investigation after preliminary checks, was in response to complaints from five private individuals that Nokia may have cheated. The preliminary checks by prosecutors specialized in business crime had attempted to uncover evidence of possible breaches by Nokia, but had not drawn any conclusions, Bieniossek said. The government of North Rhine-Westphalia state contends that financial subsidies to Nokia were contingent on the factory employing fixed numbers of staff and says that for several years the company missed the target by a margin of several hundred employees.