NANJING, July 7 -- Police in east China's Jiangsu Province have detained 12 people accused of dumping a massive amount of garbage on the bank of a lake in Suzhou City.

The suspects are accused of fly-tipping garbage since June 15 on a bank of Taihu Lake near a drug rehabilitation clinic within the Suzhou Taihu National Tourism Vacation Zone, said a spokesperson with the city's public security bureau on Wednesday.

An estimated over 20,000 tonnes of waste consisting mostly of construction materials was found across 2,400 square meters of the bank. Under police interrogation, the suspects admitted to having dumped about 12,000 tonnes.

They were caught on Friday after local maritime authorities seized eight vessels carrying 4,000 tonnes of what police suspect to be construction materials and household garbage near the bank.

Police said these vessels carried the garbage from Jiading, a suburban district in Shanghai.

Six others implicated in the case are freed on bail.