Singapore: After almost six weeks of detention and probing, the husband-wife duo of foreign investigators, Mr Peter Humphrey and Ms Yu Yingzeng were formally arrested by the Shanghai police, a statement from the family members said.

The statement published in The Wall Street Journal said that the two were suspected of breaking Chinese laws related to purchasing personal information. This arrest indicates that the police believe they have enough evidence to charge a person with a crime. The family has added in their statement that the two have lawyers and have been in touch with consular officials too.

The couple were detained by the police on July 10, but not formally arrested, the statement said. Peter Humphrey is the British co-founder of ChinaWhys and a prominent private corporate investor in China and his wife, who is reported to be the co-founder of the same company, is a US citizen and a California-educated accountant who goes by the name Ying.

These arrests were made as part of the Chinese police investigations into the bribery allegations made against British drug maker, GlaxoSmithKline PLC. The report established business links between the couple from ChinaWhys and those alleged in the GlaxoSmithKline bribery case, however, Mr Humphrey's current status with the drug maker in China is not clear.

"We only know that Ying and Peter did investigative work on corruption within foreign companies. As corruption is high on the schedule of China's government, the incarceration of Ying and Peter seems to be contradictory to China's policy in itself," the statement said.

Responding to the allegations, GSK has in its official statements accepted that some of its China executives may have violated Chinese law and company policy and that the company is cooperating with Chinese officials. The statement went on to explain that the two are being treated well but said that Mr Humphrey has a medical condition that requires monitoring.