SAN DIEGO (NEXSTAR) — The Navy says it will decommission a warship docked off San Diego after suspected arson caused extensive damage, making it too expensive to restore. Officials said Monday that fully repairing the USS Bonhomme Richard to warfighting capabilities would cost $2.5 billion to $3 billion and take five to seven years.

The Wasp-class amphibious assault ship burned for more than four days in July and was the Navy’s worst U.S. warship fire outside of combat in recent memory.

A senior defense official said in August that arson was suspected as the cause of fire and that a sailor was questioned as a potential suspect. All investigations associated with the fire onboard LHD 6 remain ongoing, according to the Navy.

“We did not come to this decision lightly,” said Secretary of the Navy Kenneth J. Braithwaite. “Following an extensive material assessment in which various courses of action were considered and evaluated, we came to the conclusion that it is not fiscally responsible to restore her.

“Although it saddens me that it is not cost effective to bring her back, I know this ship’s legacy will continue to live on through the brave men and women who fought so hard to save her, as well as the Sailors and Marines who served aboard her during her 22-year history,” Braithwaite said.

After the blaze, the Navy conducted an assessment that concluded the cost to restore the Bonhomme Richard could exceed $3 billion and require between five and seven years to complete.

The Navy also examined rebuilding the ship for alternate purposes and determined that the cost could exceed $1 billion, which is as much or more than a new-construction hospital ship, submarine tender, or command-and-control ship, according to a release from the Navy.

The Associated Press contributed to this report.