No survivors have been found nor bodies reported recovered.
"A decision to suspend searching without finding survivors is extremely difficult given the depth of its impact. ... Our thoughts and prayers are with Marine Corps helicopter squadron and particularly with families and loved ones of those missing," said Coast Guard Capt. Jim Jenkins in a written statement.
A witness last Thursday saw a fireball in midair; another reported seeing a flare. The U.S. Marine Corps notified the the Coast Guard that two CH-53 copters, carrying six men each, were missing. A search ensued involving the Navy, the National Guard, as well as Hawaii fire, police and Ocean Safety.
When the search is officially suspended at sunset Tuesday in Hawaii, a total of 130 rescue personnel will have covered 40,530 nautical square miles, an area about the size of Florida, in a 115-hour search effort, the Coast Guard said.
Any follow-up actions will be left up to the Marine Corps.
No mayday call received
The 12 missing Marines and their helicopters were on a training flight when they all appeared to go down. No mayday call was received, just word that something had gone wrong, the Coast Guard said.
Searchers spotted a fire and debris field, including an empty life raft, about two and a half miles north of Haleiwa Beach and later found floating pieces of debris consistent with military aircraft.
Eventually, all four life rafts
believed to be on board were retrieved.
"There is no indication from the sightings that any survivors have been aboard any of the life rafts," the Coast Guard said after four days of searching.
A Navy ship equipped with sonar arrived Sunday and conducted an underwater search. No additional debris was sighted. Searchers overlapped each others' areas to provide multiple perspectives and put fresh eyes on them.
The Coast Guard asked people along the coast to alert the Marines if they found any debris. The area is a popular surfing destination, and surfers were told to avoid any debris in the water to prevent injuries.
Corps names Marines
The Marine Corps has named
the 12 missing men. Base Hawaii named them as:
Maj. Shawn M. Campbell, 41, College Station, Texas
Cpl. Matthew R. Drown, 23, Spring, Texas
Lance Cpl. Ty L. Hart, 21, Aumsville, Oregon
Cpl. Thomas J. Jardas, 22, Fort Myers, Florida
Capt. Brian T. Kennedy, 31, Philadelphia
Cpl. Christopher J. Orlando, 23, Hingham, Massachusetts
Capt. Kevin T. Roche, 30, St. Louis
Sgt. Dillon J. Semolina, 24, Chaska, Minnesota
Sgt. Adam C. Schoeller, 25, Gardners, Pennsylvania
Sgt. Jeffrey A. Sempler, 22, Woodruff, South Carolina
Capt. Steven R. Torbert, 29, Florence, Alabama
Sgt. William J. Turner, 25, Florala, Alabama
Loved ones of missing
Semolina's high school principal said he heard Friday about the crash.
"You know my heart dropped there," Matt Schoen told CNN affiliate WCCO. "It was not a good feeling and again you immediately turn to hope and prayers and thoughts that there is a successful rescue mission."
He said Semolina was "a great kid. He always was jovial. He always joked around he had a great smile on his face," Schoen said.
Schoeller's family released a statement. "We value all of the thoughts and prayers offered up on our behalf during this very difficult time."
Orlando's family asked for prayers for him and the other missing Marines. "We would like to thank everyone who continues to pray and send their expressions of concern and love," they said.
Roche's family described him as a passionate Marine. "We are grateful to everyone involved in the rescue," they said in a statement.
Campbell's mother, Donna McGrew, said a Marine officer visited her at home to brief her. Campbell has a wife and four children, and has done three tours of duty in the Middle East.
"My heart just breaks; there are 11 other families going through this now. God bless them," McGrew said.