The BBC reports that there had been a massive spam attack against China’s mobile users, affecting more than 200 million China Mobile and China Unicom subscribers. Almost half of China’s mobile phone user population received unwanted text messages from seven online advertising firms, one of which included NASDAQ-listed Focus Media, according to the Xinhua news agency.

China’s State Council stated that it is thoroughly investigating the said incident. “We urge parties concerned to beef up self-scrutiny to correct their wrongdoing, which is profit-seeking in defiance of public interests,” Liu Yue, deputy head of the State Council’s Office for Rectifying Malpractice, said in a report posted on the Web site of the State Council.

This incident sparked anger from target consumers and the Chinese government, and has drawn apologies from the said major advertiser and the country’s biggest mobile phone carrier, China Mobile. Both cell phone carriers have set up support hotlines to address consumer complaints. The Chinese government and companies, on the other hand, say they are working to standardize regulations on identifying and blocking online and text spam messages.