Red China

The same stretch of Yellow River turned red a month ago (Photo - AP)

A stretch of China's Yellow River turned red for the second time in a month because of pollution, media says.... Local environmental officials said the red plume of water "very possibly" came from a station that provides heating for Lanzhou residents.

The plant had added a red dye to its water to prevent people from siphoning off the hot water from the pipes it used, officials were quoted by Chinese media as saying.

Tests found the dye was not toxic, and the spill lasted for around an hour, Xinhua news agency reports. Some 21,000 chemical factories are believed to be located along China's rivers and coastline - more than half on the Yellow and Yangtze rivers, which are relied upon by millions of people.

Could it have been a government-sponsored AIDS-awareness stunt...?

There are fears of a serious Aids epidemic in China (Photo - Getty Images)

China has announced a big jump in reported cases of HIV/Aids, officials and the state media have said. More than 180,000 people are now confirmed to have the infection, a rise of nearly 40,000 cases in a year.

A total of 183,733 cases have been reported so far this year, up from 144,089 last year, according to health ministry figures. The ministry has attributed 37% of the reported cases to drug abuse, and 28% to unsafe sex.