China is investigating a spam attack after almost half of China's mobile phone users received unwanted text messages from advertisers.
Text messages were sent to more than 200 million mobile phone users through China Mobile, and its smaller rival China Unicom. Both mobile phone companies have set up hotlines to handle consumer complaints.
China Mobile has apologised for loopholes that allowed the spread of spam text messages. It has promised to block text messages originating from seven online advertising firms.
The Chinese State Council Office for Rectifying Malpractice has urged the parties concerned to strengthen self-scrutiny to correct their wrongdoing, which is profit-driven in defiance of public interests.
The latest attack on mobile phone spam came to light after an investigation by state-run China Central Television, timed for World Consumer Rights Day on March 15.