Police in Florida say a man who did time in prison a decade ago on firearms violations gunned down his six grandchildren and his daughter before turning a weapon on himself.

Authorities say Don Spirit, 51, called 911 on Thursday to report that he might harm himself or others. When a sheriff's deputy arrived, Spirit fatally shot himself. The deputy subsequently found the bodies of his seven victims "all over on the property," at the rural home in the town of Bell, Gilchrist County Sheriff Robert Schultz said.

"There's still a lot of unanswered questions. There's going to be questions that we're never going to get answered," Schultz said, according to The Associated Press.

The sheriff did not say if the 28-year-old victim, identified as Sarah Lorraine Spirit, was the mother of any of the slain children — two boys and four girls.

He declined to say what type of weapon was used in the mass slaying.

Schultz is quoted by Bay News 9 as saying that Spirit had served a minimum prison sentence for a felony firearms violation that resulted from the 2001 shooting death of his 8-year-old son, apparently in a hunting accident.

According to the Tampa news station: "Spirit's three years in prison came after pleading guilty to accidentally shooting his son Kyle, 8, on Nov. 14, 2001, during a hunting trip to Three Lakes Wildlife Management Area near Kenansville."

Update at 11:45 a.m. ET: Authorities: Still No Motive

The Sun Sentinel writes:

"[After] investigating through the night, Gilchrist County deputies still don't know why" Spirit opened fire on his family."At a news conference Friday morning, Gilchrist County School District Superintendent Rob Rankin said at least 25 grief counselors were sent to local schools, including the one attended by the victims, Bell Elementary."'It hurt me to be on campus and see the kids feeling the way they did this morning,' Rankin said. 'It's devastating to our school.'"Copyright 2016 NPR. To see more, visit http://www.npr.org/.