The Baltimore third-grader who suffered serious head injuries in a fall at school last week and later died apparently felt ill shortly before he was hurt, but it is unclear how he sustained a fractured skull, according to an attorney for the boy’s family.

Darius Clark, 9, apparently fell in a hallway about 1 p.m. Sept. 24. When school officials found him, he was taken to the Gwynns Falls Elementary health office and later to Johns Hopkins Hospital, according to Baltimore City Public Schools officials. He died Tuesday night as a result of a skull fracture and internal bleeding, according to the family’s attorney.

Tom Yost, the lawyer who said that he is representing Darius’s family, said there are many more questions than answers about what happened to the boy at the elementary school in West Baltimore. It doesn’t make sense that he could have suffered such a traumatic head injury simply by falling down, Yost said.

“Something else had to happen; we just don’t know what it is,” he said. Yost said he has sent a letter asking the school not to erase footage from surveillance cameras, in the hopes that the video can provide some answers.

The boy’s mother received a phone call from the school at 1:31 p.m., according to Yost. She was told that Darius had been in an accident and that the school was calling an ambulance.

She immediately went to ­Gwynns Falls and found her son sitting in a chair in an office, “slumped over and not responsive,” Yost said. An ambulance took him to Johns Hopkins Hospital, where surgeons operated but could not save him.

Doctors told the boy’s family that he had a fractured skull and was bleeding from his brain, Yost said.

“The doctor at Hopkins explained to mom that this is what you’d expect to see after a car accident at 65 miles per hour,” Yost said. “Just falling down won’t do it.”

Yost said the family is concerned about the length of time between the boy’s accident and his arrival at the hospital, but whether a quicker response might have saved him will not be clear until an autopsy is performed.

Darius had complained during lunchtime of feeling ill, school officials told his mother, according to Yost. The boy got permission to leave the cafeteria to go to the bathroom, but he did not return. He was found barely responsive outside the school’s gym, Yost said, and when an administrator asked him what happened, he said he had fallen and could not move because his legs felt funny.

The lunch period usually ends at 1:05 p.m., Yost said, so the family believes that the incident must have happened before then.

Baltimore Police spokesman Lt. T.J. Smith said homicide detectives are investigating the ­9-year-old’s death and have found that he “suffered a traumatic head injury as a result of a fall.”

“It’s just an absolutely tragic situation,” Smith said in an interview Thursday, adding that the medical examiner has made a preliminary determination that the child’s death was an accident.

Gwynns Falls Elementary serves more than 420 students from pre-kindergarten through fifth grade, according to the school’s Web site.

The school system did not provide additional information in a statement Wednesday, and spokeswoman Edie House Foster said that no further information was available late Wednesday afternoon.