Search and rescue officials looking for 12 Marines who went missing after their helicopters reportedly collided late Thursday, off the coast of the Hawaiian island of Oahu, found debris Sunday that may have been from the crashed helicopters, the Coast Guard said, according to NBC News. Officials had expanded the search for the missing Marines Sunday.

Coast Guard Capt. Jim Jenkins held a news conference Sunday and said that the debris found was "consistent" with the model of the aircraft — CH-53 — flown by the Marines. Jenkins, however, did not identify the content of the debris, which was found on the North Shore of Oahu.

“It's coming together, being consolidated by the Marine Corps for a subsequent investigation” into the cause of the crash, Jenkins said, according to NBC News. The search included a Navy warship, a Coast Guard cutter, helicopters, Jet Ski teams and several other Marines.

Jenkins added that though there was no indication of any survivors from the crash, the search and rescue mission was continuing. He said, according to NBC News: “We are dedicated to trying to locate and bring those service members back.”

The two helicopters had been training before the crash and officials said that there was no mayday call before the apparent collision. Coast Guard spokesman Lt. Scott Carr said that the only thing known was that something had gone wrong.

A report by CNN said that a civilian had informed the authorities of seeing a fireball, soon after which another person reported seeing a flare. A fire and debris field was found over 2 miles north of Haleiwa Beach, along with an empty life raft.

The 12 missing Marines have been identified by the Marine Corps Hawaii Base. They were:

Maj. Shawn M. Campbell, 41, College Station, Texas

Capt. Brian T. Kennedy, 31, Philadelphia

Capt. Kevin T. Roche, 30, St. Louis

Capt. Steven R. Torbert, 29, Florence, Alabama

Sgt. Dillon J. Semolina, 24, Chaska, Minnesota

Sgt. Adam C. Schoeller, 25, Gardners, Pennsylvania

Sgt. Jeffrey A. Sempler, 22, Woodruff, South Carolina

Sgt. William J. Turner, 25, Florala, Alabama

Cpl. Matthew R. Drown, 23, Spring, Texas

Cpl. Thomas J. Jardas, 22, Fort Myers, Florida

Cpl. Christopher J. Orlando, 23, Hingham, Massachusetts

Lance Cpl. Ty L. Hart, 21, Aumsville, Oregon

Capt. Roche’s family, said in a statement, according to the Associated Press: “We believe the Marines and Coast Guard are doing everything they can to bring Kevin and his fellow Marines home safely, and we are grateful to everyone involved in the rescue.”

Sgt. Schoeller's family also released a statement, and said, according to CNN, that they were optimistic. “There are thousands praying for a positive outcome for these Marines, and the search and rescue efforts. We value all of the thoughts and prayers offered up on our behalf during this very difficult time.”

Cpl. Orlando's family, said in a statement, according to CNN: “We would like to thank everyone who continues to pray and send their expressions of concern and love for the safe return of United States Marine Corps Corporal Christopher Orlando and his fellow Marines.”