BEIJING, March 23 (Xinhua)-- A scandal which has seen half China's mobile phone users spammed with unwanted text messages has drawn the ire of the government, which has vowed to fight against the spam texters and promises to expose more of them in the future.

    China's State Council said on Sunday it is making a thorough investigation.

    The State Council also pointed the finger at greed as the motivating force behind the spammers. "We urge parties concerned to beef up self-scrutiny to correct their wrongdoing, which is profit driven in defiance of public interests," said deputy head of the State Council Office for Rectifying Malpractice Liu Yue.

    "Despite of the difficulties, we are determined to sort the problem out, which is closely linked with people's interests regardless of the stakeholder behind it" he said.

    The comment came days after China Mobile apologized for its management loopholes that allowed the spread of spam text messages to nearly half of the country's mobile phone users.

    The country's largest mobile operator has vowed to block short messages originating from the seven condemned online advertising firms last Wednesday.

    The Ministry of Information Industry (MII) is working with other related departments to spell out rules to standardize the online and text advertising market, said the official in charge of information security in MII, Zhong Zhihong.

    On the technical front, it is not difficult for mobile operators to block the rogue messages, Zhong said, reiterating the telecom operators should play their part in the clean-up campaign.

    The seven online advertising firms, which included the Nasdaq-listed Focus Media, arbitrarily sent commercial text messages to over 200 million mobile phone users whose personal information was fully controlled by the companies, through the two operators, China Mobile and China Unicom.

    This aroused anger among the target consumers and drew fierce public complaints and condemnation in the annual exposure program on China Central Television (CCTV) on March 15, World Consumer Rights Day.

    "As the mobile operator, we have the obligation to block spam text messages. We hold an unavoidable responsibility in this case," marketing operations manager Xu Ming said in response to the CCTV show.

    China has 555 million mobile phone subscribers whose personal information is easily traded between sellers who require buyers to leave their personal information and online ad companies who can send junk messages to a target group using this information.