MV-22B Osprey aircraft.Photo: Gisele Tellier/GettyA military aircraft crashed in California with five Marines on board, all of whom have died, officials confirmed.The U.S. Marines announced that an MV-22B Osprey aircraft belonging to the 3rd Marine Aircraft Wing went down on Wednesday. All five individuals were confirmed to have died “following an aviation mishap” that occurred during a training mission, officials said in apress releaseon Thursday.“We mourn the loss of our Marines in this tragic mishap. Our hearts go out to their families and friends as they cope with this tragedy,” Maj. Gen. Bradford J. Gering said in a statement.The identities of the Marines have yet to be released.An investigation is underway, officials say, noting that equipment recovery efforts have already begun.In aseries of tweets, the Marines previously said the crash happened near Glamis in Southern California around 12:25 p.m. PT Wednesday.The U.S. Marines did not immediately respond to PEOPLE’s request for comment.Never miss a story — sign up forPEOPLE’s free daily newsletterto stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human-interest stories.Intheir initial tweetabout the news, the Marines addressed “social media rumors” about the aircraft’s contents.“Contrary to social media rumors, there was no nuclear material on board the aircraft,” the branch said. “More information will be made available as we receive it.““We are awaiting confirmation of the status of the five Marines who were onboard the aircraft, which was stationed at MCAS Camp Pendleton with Marine Aircraft Group 39,” officials addedin another tweet.As for the aircraft’s technical capabilities, theAssociated Pressreported “the tilt-rotor aircraft can take off and land as a helicopter but transit as a turboprop aircraft.“In another message, the Marines said they"ask for the public’s patienceas we work diligently with first responders and the unit involved to identify what occurred this afternoon.”

MV-22B Osprey aircraft.Photo: Gisele Tellier/Getty

An MV-22B Osprey aircraft takes off from the USS Bataan on January 13, 2012 near Catania, Italy. The Bataan, part of the Amphibious Readiness Group, deployed in support of Operation Odyssey Dawn in March 2011 from Norfolk, Virginia and has supported the Fifth and Sixth Fleet areas of operations. Now heading home, the deployment has been one of the longest in U.S. Navy history.

A military aircraft crashed in California with five Marines on board, all of whom have died, officials confirmed.The U.S. Marines announced that an MV-22B Osprey aircraft belonging to the 3rd Marine Aircraft Wing went down on Wednesday. All five individuals were confirmed to have died “following an aviation mishap” that occurred during a training mission, officials said in apress releaseon Thursday.“We mourn the loss of our Marines in this tragic mishap. Our hearts go out to their families and friends as they cope with this tragedy,” Maj. Gen. Bradford J. Gering said in a statement.The identities of the Marines have yet to be released.An investigation is underway, officials say, noting that equipment recovery efforts have already begun.In aseries of tweets, the Marines previously said the crash happened near Glamis in Southern California around 12:25 p.m. PT Wednesday.The U.S. Marines did not immediately respond to PEOPLE’s request for comment.Never miss a story — sign up forPEOPLE’s free daily newsletterto stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human-interest stories.Intheir initial tweetabout the news, the Marines addressed “social media rumors” about the aircraft’s contents.“Contrary to social media rumors, there was no nuclear material on board the aircraft,” the branch said. “More information will be made available as we receive it.““We are awaiting confirmation of the status of the five Marines who were onboard the aircraft, which was stationed at MCAS Camp Pendleton with Marine Aircraft Group 39,” officials addedin another tweet.As for the aircraft’s technical capabilities, theAssociated Pressreported “the tilt-rotor aircraft can take off and land as a helicopter but transit as a turboprop aircraft.“In another message, the Marines said they"ask for the public’s patienceas we work diligently with first responders and the unit involved to identify what occurred this afternoon.”

A military aircraft crashed in California with five Marines on board, all of whom have died, officials confirmed.

The U.S. Marines announced that an MV-22B Osprey aircraft belonging to the 3rd Marine Aircraft Wing went down on Wednesday. All five individuals were confirmed to have died “following an aviation mishap” that occurred during a training mission, officials said in apress releaseon Thursday.

“We mourn the loss of our Marines in this tragic mishap. Our hearts go out to their families and friends as they cope with this tragedy,” Maj. Gen. Bradford J. Gering said in a statement.

The identities of the Marines have yet to be released.

An investigation is underway, officials say, noting that equipment recovery efforts have already begun.

In aseries of tweets, the Marines previously said the crash happened near Glamis in Southern California around 12:25 p.m. PT Wednesday.

The U.S. Marines did not immediately respond to PEOPLE’s request for comment.

Never miss a story — sign up forPEOPLE’s free daily newsletterto stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human-interest stories.

Intheir initial tweetabout the news, the Marines addressed “social media rumors” about the aircraft’s contents.

“Contrary to social media rumors, there was no nuclear material on board the aircraft,” the branch said. “More information will be made available as we receive it.”

“We are awaiting confirmation of the status of the five Marines who were onboard the aircraft, which was stationed at MCAS Camp Pendleton with Marine Aircraft Group 39,” officials addedin another tweet.

As for the aircraft’s technical capabilities, theAssociated Pressreported “the tilt-rotor aircraft can take off and land as a helicopter but transit as a turboprop aircraft.”

In another message, the Marines said they"ask for the public’s patienceas we work diligently with first responders and the unit involved to identify what occurred this afternoon.”

source: people.com