BEIJING (AP) -- Tom Online Inc., a Chinese Internet portal and wireless provider, said Tuesday it swung to a second-quarter loss as revenue from wireless Internet service and online advertising plunged.

Tom Online posted a loss of US$9.6 million (euro7 million) for the quarter ending June 30, compared with a profit of US$11.8 million (euro8.5 million) in the year-earlier quarter. Revenue fell more than 30 percent to US$34.4 million (euro24.8 million).

The company offers wireless Internet data services through China Mobile and China Unicom, which control the networks through which most services are provided to mobile users in China.

In May the Chinese telecom carrier started to display a reminder of fees to wireless application protocol, or WAP, users when they try to browse a WAP page.

China Mobile also began promoting only its own wireless value-added services on the embedded menus of handsets customized for China Mobile under its alliances with selected handset makers.

Citing the adverse effect of China Mobile's policies, Tom Online wrote down the value of goodwill on its books by US$6.8 million (euro4.9 million) in the quarter. Without that charge, the company would have lost US$2.7 million (euro1.9 million).