CHATTANOOGA, Tenn. -- At least six children were killed in a school bus crash in Chattanooga, Tennessee, on Monday, a spokeswoman for the Hamilton County District Attorney's Office said.
Chattanooga Police Chief Fred Fletcher, though, declined to confirm the number of fatalities at a news conference on Monday.
Fletcher said the bus, which was carrying 35 students in kindergarten through fifth-grade from Woodmore Elementary School, turned over on its side and struck a tree.
Authorities received a call about the crash just before 3:30 p.m., Fletcher said.
At least 23 people were transported to local hospitals after the single-vehicle crash, authorities said.
"Certainly, speed is being investigated very, very strongly as a factor in this crash," Fletcher said, adding that the investigation was still in an early stage.
He added that driving conditions were clear and dry.
Fletcher said, "A warrant has been issued to remove the informational box and videos" from the bus.
He said the families of victims are still being notified.
"Our thoughts, our prayers and all of our efforts are with the families of these children and others impacted by this tragedy," Fletcher said.
Melydia Clewell, the spokeswoman from the district attorney's office, said at least five children died on the scene, and one died at a hospital.
Fletcher called the crash scene "a complicated crime scene."
Earlier, Fletcher said, a school bus crash "is every public safety professional's worst nightmare but it's also the thing that we all train for," according to WTVC.
The bus driver is cooperative and talking to investigators, police said.
A tweet from the Chattanooga Fire Department showed the bus on its side and up against a tree as emergency officials extricated the last patient through the back door.
WTVC reported that lines of donors stretched out the door of the Chattanooga Blood Assurance, the local blood bank, which extended its hours Monday night because of the bus crash.