HONG KONG (Deutsche Presse-Agentur) -- Chinese mothers who travel to Hong Kong to give birth to a second child are being fined on their return for breaching Beijing's one-child policy, a radio report said Tuesday.

Mothers from several Chinese cities have already been fined for cross-border births, Zheng Feng, director of family planning in Guangdong province, was quoted as saying by RTHK radio in Hong Kong.

Tens of thousands of Chinese women a year travel to Hong Kong to give birth, some to avoid fines for second children under China's one-child policy.

Zheng did not say how much the mothers were fined but government-run RTHK said fines for violating the policy could be up to six times the average annual per capita disposable income of residents' home towns.

The number of women coming to Hong Kong from China to give birth has soared since cross-border travel restrictions were eased from 2003 onwards.

In 2010, some 42,000 of Hong Kong's 89,000 births were to women from the mainland, whose children qualify for residency, free education and health care if born in the city.

Amid rising discontent over the influx and its effect on public health services, the Hong Kong government has capped the number of Chinese women allowed to give birth in the city in 2012 at 34,000.

Copyright 2012 dpa Deutsche Presse-Agentur GmbH