Five Marines who were on a helicopter that crashed outside San Diego have been confirmed dead, the military announced.

The military confirmed on Thursday that five U.S. Marines who were on a helicopter that crashed during a stormy weather in the mountains near San Diego have died.

The CH-53E Super Stallion disappeared late Tuesday night while returning to Marine Corps Air Station Miramar in San Diego after training at Creech Air Force Base, northwest of Las Vegas, according to authorities.

Maj. Gen. Michael J. Borgschulte, commander of 3rd Marine Aircraft Wing, announced the loss of five exceptional Marines from 3d Marine Aircraft Wing and the “Flying Tigers” with a heavy heart and profound sadness.

The names of the Marines were not immediately released.

Borgshulte stated, "We express our deepest condolences to the families of our fallen Marines and pledge to provide them with unwavering support and care during this challenging period. We recognize that, despite the inherent risks of military service, any loss of life is always deeply felt."

An investigation into the crash is underway and efforts to recover the remains of the five have commenced, as per the statement.

The wing's spokesperson, Capt. Stephanie Leguizamon, admitted she had minimal details beyond the statement.

The crash site has been a contentious issue for searchers due to its cold temperatures.

In a statement, President Biden and first lady Jill Biden expressed their grief over the deaths of the Marines.

Biden stated that our service members embody the greatest values of our country, and these five Marines were no exception. As the Department of Defense investigates the incident, we express our heartfelt sympathies to the families, squadron, and U.S. Marine Corps for the loss of five exceptional warriors.

According to Mike Cornette of the California Department of Forestry and Fire Protection, the last known contact with the helicopter was at approximately 11:30 p.m. on Tuesday. The location was determined based on a "ping" reported to a Cal Fire dispatch center.

Near Pine Valley, an hour from San Diego, the craft was discovered on Wednesday morning.

The aircraft, which crashed during a storm in the Southern California mountains, was found by civilian authorities after a search on the ground and in the air, approximately 45 miles (72 kilometers) from San Diego.

The helicopter, designed for harsh conditions, disappeared during an historic storm that brought heavy snow and record rain to California. Searchers were forced to navigate through heavy snow to locate the helicopter after more rain and snow fell Wednesday night.

Five Marines were assigned to Marine Heavy Helicopter Squadron 361, Marine Aircraft Group 16, 3rd Marine Aircraft Wing, according to a military statement.

According to a U.S. Navy website, the Super Stallion can carry up to 40 people, but its normal crew consists of four members: a pilot, copilot, crew chief, and mechanic/gunner.

The military collaborated with various federal, state, and local agencies, including the U.S. Forest Service, U.S. Border Patrol, San Diego County Sheriff's Department, and the state Civil Air Patrol.

The task was challenging due to the weather and rugged terrain in Pine Valley, which experienced heavy snowfall of up to 8 inches (20 centimeters) within hours Tuesday night and Wednesday night, according to forecasters.

Cuyamaca Peak, San Diego County's second highest mountain at 6,512 feet (1,985 meters), is located near the Cleveland National Forest, which encompasses 720 square miles (1,860 square kilometers) of steep, rocky terrain with limited trails.

The Super Stallion is the largest military helicopter and has been used by the Marines for heavy-lifting tasks globally for over three decades, with over 130 in operation.

The aircraft, equipped with GPS, infrared radar, and other equipment, has carried out a wide range of military operations in Beirut, Somalia, the Persian Gulf, Afghanistan, Iraq, and Libya, as stated on the U.S. Navy website.

The Super Stallion, measuring about 99 feet (30 meters) in length, is capable of transporting troops and equipment from ships to shore, delivering supplies, and launching amphibious assaults.

The Super Stallion, nicknamed the “hurricane maker” due to its three engines' downwash, has a 50-mile range and can carry up to 55 troops or 16 tons of cargo inside and outside the cabin.

Nearly 35 tons (31,638 kilograms) is the maximum weight of a helicopter with an external load.

In January 1990, two CH-53E helicopters were employed in Mogadishu, Somalia, to rescue American and foreign allies from the U.S. embassy during the civil war.

Several deadly accidents involving helicopters have occurred. In 2018, four Marines from Miramar died when their Super Stallion crashed near El Centro, near the California-Mexico border, during a training mission. The Marine Corps ruled out pilot error for the accident. The victims’ families later sued two companies they alleged provided a defective part that they blamed for the crash.

In 2005, a Super Stallion crashed in a sandstorm in Iraq, resulting in the death of 31 people on board. This unfortunate event, attributed to pilot error, was the deadliest loss of U.S. troops during the war.