Apple supplier Biel Crystal violates workers rights: HK activists BEIJING (Reuters) - Biel Crystal Manufactory Ltd, a Hong-Kong based company that makes screens for Apple Inc, is violating workers' rights at its Chinese factories, a Hong Kong rights group alleged in a report. The Students & Scholars Against Corporate Misbehaviour (SACOM) report said Biel Crystal, which makes iPhone screens, requires its employees to work 11-hour shifts, seven days a week, with only one day off each month. Employees are also often injured and not given reasonable compensation and have to sign blank contracts, the report said. At least five workers at the firm's Guangdong factory in mainland China committed suicide since 2011, it added. There was no immediate comment from Biel Crystal on the report. Kitty Potter, a spokeswoman for Apple in Greater China, said that the U.S. company "investigates such cases." "We insist that our suppliers provide safe working conditions, treat workers with dignity and respect, and use environmentally responsible manufacturing processes wherever Apple products are made," Apple said in a statement sent to Reuters in response to the SACOM report. Every year Apple inspects more factories, going deeper into the supply chain and raising the bar for our suppliers. In 2012 we conducted 393 audits at supplier facilities around the world," it added. Biel Crystal employs more than 60,000 workers, according to the company's website, and has two factories, one in Guangdong and the other in Shenzhen. It was not immediately clear how long Biel had been an Apple supplier. Labor rights groups have in the past few years criticized the working conditions in at least two other Apple suppliers - its main manufacturing partner Foxconn Group, which is the trading name of Taiwan's Hon Hai Precision Industry, and another Taiwanese firm, Pegatron Corp. Reporting by Paul Carsten and Adam Rose; Editing by Miral Fahmy