State police followed trained dogs through the brush Friday in an area of southeastern Massachusetts where five bodies, four identified as women, have been found alongside highways since July.

Authorities suspect a serial killer may be responsible because the decomposed remains were found in a six- to eight-mile radius, in dense woods within 25 feet of Interstate 195 and Route 140, and all are believed to be women.Bristol County District Attorney Ronald A. Pina said three of the victims have been tentatively identified, but further research was being conducted. State police said one woman was strangled.

Pina has linked the discovery of the bodies, which may have been abandoned for as long as a year, to the disappearance of five women from New Bedford in recent months.