Two Long Island beachgoers found a human jawbone on the sand in an eerie discovery during their Monday evening stroll, cops said. The man and woman were walking along the beach at Smith Point County Park in Shirley, along the south shore of the island, just before 5 p.m.when they spotted the bone, police said. The pair brought the remains to a park attendant working at the beach, who called the cops, authorities said. The Suffolk County Medical Examiner determined that the remains are human, but further investigation is needed to link them to a particular person. Detectives from Suffolk County Police Homicide Squad are also investigating the finding. Anyone with information is asked to contact the detectives at 631-852-6392.The disturbing discovery comes as hearings continue for accused Gilgo Beach serial killer Rex Heuermann, 60, now charged in the killings of seven Long Island sex workers — Valerie Mack, 24; Jessica Taylor, 20; Megan Waterman, 22; Melissa Barthelemy, 24; Maureen Brainard-Barnes, 25; Sandra Costilla, 28; and Amber Lynn Costello, 27.Most of the victims’ remains were found along Ocean Parkway near Gilgo Beach – also located on the South Shore of Long Island – between December 2010 and April 2011....