Hong Kong authorities have arrested over 400 new mothers from mainland China who gave birth in the city-state, underlining the rift between Chinese women and local mothers over health and education resources.

The mainland Chinese mothers were arrested one to two days after giving birth and mostly sentenced to two months jail time. Their babies are allowed to stay with the mothers in wards with their own cribs, a spokesman for the city’s correctional services department said.

Hong Kong’s advanced health and education systems has appealed to Chinese mothers in part because it gives the newborns the right to live in the city-state. It also provides them a way to evade China’s one-child policy. But the influx of mainland mothers has raised concerns from locals that resources are being stretched and hospitals are getting overcrowded.

About 45% of some 88,000 babies born in Hong Kong were born to mainland women in 2010 while the number of pregnant mainland women attempting to cross the border is steadily mounting, increasing 3,500 over the past year, a rise of more than 80% in 2011, the Immigration Department said.

Roughly 420 women were prosecuted on charges of overstaying visas since last October and dozens of mainlanders have been jailed up to a year for assisting women to give birth in Hong Kong.

Hong Kong Chief Executive Leung Chun-ying announced in April that women from the mainland will be prohibited from giving birth in private hospitals unless they are married to a permanent resident or have valid working visas. Immigration authorities said they are closely cooperating with their mainland counterparts to curb “birth tourists”.

“To protect social resources in Hong Kong, I think it’s needed,” a department spokesman said of the crackdown.