HILLSDALE — Five persons remained hospitalized today after an accident that killed three children late Sunday afternoon. Chad Crommer, 2, of Pioneer, Ohio, and Matt Fowler, 6, of 415 Railroad St., Reading, were reported in critical condition this morning at St. Vincent’s Medical Center, Toledo, Ohio. They were injured in an accident at 6:39 p.m. Sunday when Mark J. Crommer, 29, of Pioneer, Ohio, apparently ran a stop sign and collided with a vehicle driven by Larry Fowler, 24, of 415 Railroad St., Reading. The accident remains under investigation by the Hillsdale County Sheriff’s Department. Crammer was reported in fair condition this morning at Hillsdale Community Health Center. Larry Fowler was reported in serious condition at Bronson Methodist Hospital, Kalamazoo, and Greg Fowler, 4, was listed in good condition at Burgess Medical Center, Kalamazoo. Lorrain Fowler, 23, was discharged Monday from HCHC. Killed in the crash were Nicole Crommer, 6, of Pioneer, and Amy Fowler, 2, and Jason Fowler, eight months, of Reading. Their deaths bring the county’s death toll to eight for 1985.