'Very strong possibility' that suspected Michigan school shooter had weapon with him when he met with school officials hours before the attack, prosecutor says

• The suspect in a Michigan school shooting possibly had the gun with him when he met with school officials that morning.

• The meeting was called to address 15-year-old Ethan Crumbley's "concerning behavior," police said.

• Oakland County Prosecutor Karen McDonald told CNN she is still considering charging the suspect's parents.

The 15-year-old suspected gunman in a Michigan high school shooting that left four students dead and several others injured, likely had the weapon in his possession during a behavioral meeting with his parents and school officials just hours before the rampage, the county prosecutor said.

Oakland County Prosecutor Karen McDonald told CNN's Anderson Cooper there was a "very strong possibility" that sophomore Ethan Crumbley, who has been charged in the crime, was carrying the semiautomatic handgun in his backpack during the face-to-face meeting with his parents and administrators, which was called to address his "concerning behavior."

"Unfortunately he was allowed to go back to class," McDonald said. "We now know he had a weapon with him at that time, and that is simply tragic."

McDonald said students at Oxford High School were not using lockers this semester due to COVID-19, and thus, only had access to their backpacks throughout the day.

CNN reported that two teachers flagged Crumbley's concerning behavior, which prompted the meeting.

Crumbley has been charged with four counts of first-degree murder, which implies premeditation, one count of terrorism causing death, seven counts of assault with intent to murder, and 12 counts of felony firearm possession.