Ogden police Lt. Danielle Croyle could not comment on whether police have determined who wrote the note, only that their investigation is ongoing. Classes are scheduled to resume as normal on Wednesday.
Shadow Valley Elementary School got a good practice drill out of it, but hoaxes are a concern because law enforcement uses the same resources and response to every call, real or fake, Croyle said.
"When these kinds of things come in, we take them all seriously," Croyle said.
On Monday, students and staff at the Mountain View Elementary School in Layton were evacuated for most of the day when a janitor found what proved to be a real pipe bomb on the roof.
Layton police Lt. Shawn Horton described the device as a 4-inch length of ¾-inch diameter white plastic PVC pipe, filled with gunpowder and capped at both ends. All it was missing was a fuse.
Bomb experts destroyed the device. Students returned to class without incident on Tuesday, Layton police and Davis School District officials said.
Police have no suspects at this time, but detectives are screening video from 14 security cameras in hopes of identifying the person believed to have thrown the bomb onto the roof. Anyone with information on this incident is urged to contact Layton police at 801-497-8300.
Meanwhile, the FBI and Utah Highway Patrol reopened U.S. 163 in southern Utah's San Juan County early Tuesday morning after a bogus bomb threat was made to a tour bus, forcing closure of the highway for several hours late Monday.
The FBI, given the interstate and public transportation aspects of the threat, was leading the investigation. No details on the exact content of the threat, or how it was received, were released.
Beginning about 2 p.m. Monday, the highway was closed down south of Mexican Hat. The bus was about 14 miles north of the Utah-Arizona state line, in Utah's scenic Monument Valley on the Navajo Nation, when it was stopped and passengers safely evacuated.
Traffic between the Arizona border and Bluff was rerouted to U.S. 191 to the east of U.S. 163.