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A large chunk of Tucson - stretching from Midtown across the mountains to Three Points and northwest to Marana - was rattled Wednesday evening by a loud, deep boom and shaking ground. Some reported two booms.

Late Thursday afternoon, Air Force officials confirmed the noise was a sonic boom from an F-16 flying out of Luke Air Force Base near Phoenix.

The fighter jet that broke the sound barrier, causing the rumble, was flying west of Tucson near Sells on a training mission with other F-16s, a spokesperson for the base said. The F-16 was northwest of Kitt Peak, more than 60 miles from Tucson, when the sonic boom rumbled across the desert.

Only one jet broke the sound barrier. The spokesperson said the pilot was flying above the minimum altitude the go supersonic.

The planes are part of the 425th Fighter Squadron based at Luke AFB.

Thursday night, officials from a variety of local agencies said they couldn't explain the boom.

On the West Side, there were two distinct booms and the ground shook for several seconds around 7:35-7:40 p.m.

A spokesman for the Pima County Sheriff's Department said Thursday that they had ruled out Davis-Monthan Air Force Base, Luke AFB, Tucson International Airport, Southwest Gas and other gas companies and Tucson Electric Power as being related to the boom. Area copper mines were also not involved.

Hundreds of calls to 911 were placed regarding the boom, PCSD's Sgt. Tom Peine said.

An earlier earthquake in Oregon was picked up by U.S. Geological Survey sensors in Tucson, but no local earthquake was been reported.

Comments on the TucsonSentinel.com Facebook page and elsewhere on social media indicated that the boom and shaking ground were experienced across a wide swath of the Tucson area.

A mysterious boom was also heard Wednesday morning in San Diego, media there reported.

Last April, a sonic boom caused by an Air Force Thunderbird pilot warming up for the D-M air show caused more than $22,000 in damage. The pilot of that plane uttered "oh, crap" at the time of the boom, a USAF investigation said.

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