The weapon from a parking lot shooting early Sunday morning at CU Boulder’s Williams Village dorms was an air pistol that shoots BBs, according to the University of Colorado Police Department.

At approximately 3 a.m., CU police responded to a noise complaint at Weber Hall and were breaking up a large party when they received reports of shots fired in a parking lot outside the building, according to a 7 a.m. campus emergency alert.

At 4:24 a.m., CU released an emergency alert reporting the shooting and imposed a shelter-in-place order. By 5:25 a.m., four suspects, three of whom are juveniles, were identified and arrested and the shelter-in-place was lifted, officials said. The suspects are not affiliated with the university and no serious injuries were reported, according to police.

According to an update from CUPD Monday, the weapon in question was later determined to be an air pistol that shoots BBs and sounds similar to a gunshot.

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