DENVER (KDVR) — The threats made to schools in districts across Colorado Wednesday morning were seemingly made in alphabetical order, FOX31 found.

In some of the cases, sounds of gunfire were played in the background of the calls.

The first known threat made to a school was to Alamosa School District at 8:24 a.m.

Then, at 8:28 a.m., Aspen School District was called. Two minutes later, at 8:30 a.m., Aurora School District was called.

In addition to the school threats, Denver 911 received a report of a threat at FBI Denver at 9:00 a.m.

The following is a list of the school districts and police departments that dealt with false school threats Wednesday:

  • Alamosa School District (Ortega Middle School) – 8:24 a.m.
  • Aspen School District (Aspen High School) – 8:28 a.m.
  • Aurora School District (Aurora Central High School) – 8:30 a.m.
  • Boulder Valley School District (Boulder High School) – 8:33 a.m.
  • Brighton School District (Brighton High School) – 8:40 a.m.
  • Cañon City Schools (Cañon City High School) – 8:45 a.m.
  • Denver 911 – 9:00 a.m.
  • Durango School District (Durango High School) – Specific time unknown
  • Englewood Schools District (Englewood High School and Middle School) – 9:19 a.m.
  • Estes Park (Estes Park High School) – 9:23 a.m.
  • Gilpin County School District (Gilpin County School) – Specific time unknown
  • Morgan County School District Fort (Morgan High School) – 9:38 a.m.
  • Roaring Fork School District (Glenwood Springs High School) – 9:45 a.m.

Several other school districts, including Littleton, Ouray and Steamboat, received shooting threats Wednesday afternoon. It does not appear as if these later threats were made alphabetically.

The FBI is investigating the calls.

FOX31 will update the list as more information becomes available.