YOKOSUKA, Japan (AP) — The mother of a U.S. Navy sailor said her son kept diving to try to save his shipmates after a collision at sea until their flooded sleeping berth began running out of air pockets, while other survivors — believing their ship was under attack — hurried to man the guns.

Mia Sykes of Raleigh, North Carolina, told The Associated Press on Sunday that her 19-year-old son, Brayden Harden, was knocked out of his bunk by the impact, and water immediately began filling the berth, after their destroyer, the USS Fitzgerald, collided with a Philippine-flagged container ship four times its size off the Japanese coast.

The ships collided about 2:20 a.m. Saturday, when the Navy said most of the 300 sailors on board would have been sleeping, and authorities have declined to speculate on a cause while the crash remains under investigation.

Sykes says her son told her that four men in his berth, including those sleeping on bunks above and below him died, while three died in the berth above his.

“They did what they were trained to do,” said Sykes, who said she hopes her son, from Herrin, Illinois, can come home to be with family as he works through what happened. “You have to realize most of them are 18, 19 and 20-year-olds living with guilt. But I told him, ‘There’s a reason you’re still here and make that count.’”

On Monday morning in Japan, the Navy’s 7th Fleet identified the seven sailors who died. Navy divers had recovered the bodies after the severely damaged Fitzgerald returned to the fleet’s home in Yokosuka, Japan, on Saturday with assistance from tug boats.

Among the seven U.S. Navy sailors who died in the Saturday collision were an Ohioan expecting to retire soon, a Maryland man his father called his best friend, and a Connecticut man described by his sister as “selfless.”

Here are snapshots of them taken from interviews of family and friends with the media:

GARY LEO REHM JR., Ohio

Fire Controlman 1st Class Gary Leo Rehm Jr., 37, was three months shy of retiring when he was killed, his cousin tells The Chronicle-Telegram in Elyria, Ohio.

Rehm was from Elyria, about 25 miles west of Cleveland, and is survived by his wife, Erin; his parents, in Virginia; and a sister in Texas, his cousin Brad Rehm said, adding that word of his death was shocking.

He enlisted in the Navy in 1998.Daniel Kahle of Chesapeake, Virginia, a Navy veteran who served with Rehm while deployed to the Persian Gulf during the Iraq war, told the newspaper he hadn’t spoken to his former colleague in years but will remember him as “a great guy” who always seemed to be smiling.

Rehm was a graduate of Oberlin High School as a Lorain County Joint Vocational School student.

NGOC T TRUONG HUYNH, Connecticut

Sonar Technician 3rd Class Ngoc T. Truong Huynh, 25, always “had the brightest smile,” his sister says. He was “selfless,” Lan Huynh told WVIT-TV of Hartford, Connecticut, and the family is coping as best they can. Huynh graduated from Watertown High School and attended Naugatuck Valley Community College before enlisting in the Navy in 2014. The family moved to Oklahoma a short time later. Connecticut’s governor has ordered flags to fly at half-staff in Huynh’s honor.

ALEC MARTIN, Maryland

Personnel Specialist 1st Class Xavier Alec Martin was trying to call his father after the vessels collided but didn’t get through, his father told WJZ-TV in Baltimore. All Darrold Martin can think of now are his son’s final moments. The 24-year-old sailor, of Halethorpe, Maryland, followed in his father’s footsteps and was quickly rising in the ranks, said Darrold Martin, who referred to his son as his best friend. “It’s very hard,” the elder Martin said. “He’s my only child, he’s all I have.”

The others killed were:

• Yeoman 3rd Class Shingo Alexander Douglass, 25, from San Diego, California

• Gunner’s Mate Seaman Dakota Kyle Rigsby, 19, from Palmyra, Virginia

• Fire Controlman 2nd Class Carlos Victor Ganzon Sibayan, 23, from Chula Vista, California

• Gunner’s Mate 2nd Class Noe Hernandez, 26, from Weslaco, Texas