Eight infants were found dead Wednesday in the northern French province of Nord, local police said, Xinhua reported.
The bodies of four newborns were discovered by a couple in the garden of their newly bought villa and the other four by local police 1 km away from the villa.
The former owners of the villa -- a middle-aged couple, were arrested immediately. Inquiry will be made on Thursday.
Local residents were horrified and shocked as they said the suspected couple had always been nice.
The case raised security concerns in the area where public order had been sound for many years.
Police said autopsies will be carried out to find the cause of the deaths.