DPS respond to report of suspected intruder with a black backpack entering a Dalton Elementary Classroom this afternoon

“I passed by there was multiple state troopers, guns drawn coming out of the back building,” Laura Hill said

  Between 3:30 to 4 PM this afternoon, the Uvalde Police Department posted on Facebook an alert about an report received about a male subject

seen enter a classroom at Dalton Elementary School and Texas Department of Public Safety had cleared the building.
  According to Uvalde City Councilman Hector R. Luevano,  he saw officers at the Dalton Early Childhood Campus approximately at 2 PM.
"I passed by. There were multiple state troopers, guns drawn coming out of the back building," Laura Hill said.
  At approximately 4:30 PM the Uvalde Hesperian received this statement from Texas DPS:
"Someone called 911 and reported seeing a male dressed in black walk into a classroom at Dalton Elementary.
Uvalde PD, DPS, and DPS CID responded and cleared all rooms and did not locate any intruders. No injuries reported."
At 6:30 PM Uvalde CISD issued the following statement about the incident to the media:
"On Monday, January 2, a school district holiday, the Dalton administration learned Uvalde Police Department received a report of a male subject wearing all black attempting to enter Dalton Elementary School. Uvalde Police Department Officers and Texas Department of Public Safety Troopers responded to the campus. Law enforcement searched the entire property and each classroom and found no evidence of anyone other than a teacher being in the building. We appreciate the swift action taken by both entities to address the report giving the all-clear for rooms and buildings.
  Upon review of camera footage, the individual was walking outside the fence and had left the property’s perimeter before the authorities arrived. The individual was not seen on camera footage on campus or entering a classroom. We are thankful this report was resolved without harming students or staff. We encourage community members, students, parents, and staff to report threats, inappropriate actions, or behaviors they witness immediately. This is one way we can all work together to keep our schools safe."
It is unclear why the Uvalde Police Department issued its first statement about the incident over an hour and a half after the incident was reported.
Also,  Was there an actual intruder on school property who gained access to a classroom or was suspect just someone walking on the perimeter of the campus?
Could the suspect who was reported to have been seen entering a classroom a teacher or a district employee? If the campus and a classroom was accessed,  how did that happen?