The Marine Corps is investigating the death of an enlisted recruit Friday at its iconic recruit depot at Parris Island in South Carolina, Marine officials said.

The death occurred during the day at the depot, where about half of the service’s recruits are trained each year, said Capt. Gregory Carroll, a Marine spokesman at the depot. The circumstances of the death were not immediately clear, but it will be examined by the Naval Criminal Investigative Service. The recruit was identified Sunday as Raheel Siddiqui, 20, of Taylor, Mich.

Marine boot camp is known for its firm treatment of recruits. There is one depot at Parris Island and one in San Diego, with all women attending training at Parris Island and all men enlisting east of the Mississippi River also going there.

A handful of recruits and staff have died at boot camp since the Sept. 11, 2001, attacks, including a drill instructor who was found dead in base housing at Parris Island in 2014. Others have died from drowning and after collapsing following exercise.

This story was updated with the name of the deceased recruit.