( CNN ) -- Five members of a family were found slain in their Beason , Illinois , home , authorities said Tuesday , and they urged people in the area to be cautious until the killer is found . Police officers stand patrol outside the Gee household late Monday evening . `` This was a brutal homicide against an entire family and we are determined to identify and arrest those responsible , '' Logan County Sheriff Steve Nichols said in a news conference . He said authorities received a 911 call about a possible shooting at the home shortly before 4:30 p.m. ( 5:30 p.m . ET ) Monday . When law enforcement officials arrived , they discovered the five bodies , Nichols said . He identified the dead as Raymond Gee , 46 ; Ruth Gee , 39 ; Justina Constant , 16 ; Dillon Constant , 14 ; and Austin Gee , 11 . One survivor , a 3-year-old girl , is in a hospital in Peoria , Illinois , he said . He did not identify the girl . The sheriff did not release the manner of death , but said autopsies were under way Tuesday . He warned people in the area to be cautious . `` Until we find this person , we would consider this person armed and dangerous , '' Nichols said . He did not release any further details , and it was not immediately clear if authorities had identified a suspect . `` Leads have been developed and are being vigorously pursued , '' he said , without elaborating . Beason is about 45 miles northeast of Springfield , Illinois . CNN 's Kara Devlin contributed to this report .
`` This was a brutal homicide against an entire family , '' sheriff says . One survivor , a 3-year-old girl , hospitalized in Peoria , Illinois . Killings occurred in Beason , Illinois , about 45 miles northeast of Springfield . The killer is still at large and has not been identified by authorities.