( CNN ) -- The search is over for a California family who disappeared under mystifying circumstances three years ago . Authorities confirmed the identity of two of four sets of remains found Monday in the California desert near Victorville as those of Joseph McStay and his wife Summer , San Bernardino County Sheriff John McMahon said Friday . They were identified through dental records , he said . Two other remains found nearby are believed to be those of their sons Joseph and Gianni , McMahon said . He said positive identification will be done through DNA testing . The four were killed , McMahon said . No suspects have been identified and the sheriff did not elaborate on how they died . Some family members became emotional during Friday afternoon 's news conference . `` It gives us courage to know they are together , and they 're in a better place , '' said Joseph 's younger brother Mike McStay , choking back tears . `` It 's been a tough road . '' A motorcyclist reported finding possible skeletal remains Monday in an area not far from Interstate 15 near Victorville , according to the Sheriff 's Department . Police found two shallow grave sites , with two sets of remains in each grave , McMahon said . February 4 , 2010 was the last day anyone saw the family or heard from them . When police entered their Southern California house more than 10 days later , they found eggs on the kitchen counter and bowls of popcorn in the living room . Their two dogs were also in the home . But not a single trace of the McStays . The McStays lived in Fallbrook , about 18 miles from the Pacific Coast and some 50 miles north of San Diego . The family 's locked and abandoned Isuzu Trooper was located February 8 , 2010 , in San Ysidro , California , just two blocks from the border . Surveillance video taken that night shows a family fitting the description of the McStays walking into Mexico . But from there the trail goes cold . The sheriff said his office said it will look at this crime from the beginning , and will work with the FBI to find the suspects . Although investigators said someone had been researching travel to Mexico on the family 's home computer , the McStays ' sudden disappearance and the fact that their credit cards and bank accounts went unused raised suspicions . When they disappeared three years ago , Joseph was 40 , his wife , Summer , was 43 , and their children were 4 and 3 years old . `` I 've been in this business for over 35 years , but I 've never seen anything like this , '' Lt. Dennis Brugos of the San Diego Sheriff 's Department told CNN shortly after the disappearance . FBI taking over investigation .
NEW : The couple , who disappeared with their small children , were killed , authorities say . NEW : Remains were identified through dental records . Two other sets of remains also found might be couple 's sons , authorities say . Joseph and Mary McStay and their sons disappeared in 2010 .