FILE: May 2, 2012: A display at the Charleston Museum in Charleston, S.C., shows an 1862 Harpers Weekly article about Robert Smalls and the CSS Planter. Researchers announced on May 13, 2014 that they believe they have found the wreck of the Planter on the South Carolina coast. AP

CHARLESTON, S.C. Researchers think they have found the wreck of the iconic Civil War vessel the Planter the Confederate ammunition ship commandeered by the slave Robert Smalls, who steamed it out of Charleston and surrendered it to the Union .

Archaeologists with the National Marne Sanctuary said Tuesday they have found what is thought to be the wreck of the side wheel steamer buried under about 15 feet of sand just offshore at Cape Romain, northeast of Charleston.

They released a report outlining their findings on the anniversary of the day in 1862 when Smalls took the vessel.

Smalls would return to Charleston a year later to pilot a Union ironclad in an attack on Fort Sumter. After the war, he served in the South Carolina General Assembly, the U.S. Congress and as a federal customs inspector.

Bruce Terrell, a maritime archaeologist and historian, said scientists used old and newspaper accounts to identify the general area where the Planter was thought to have wrecked in a storm in 1876, eleven years after the war ended.

Using a magnetometer, an instrument that can detect metal beneath the ground, they found a number of metal objects seeming to correspond to the wreck. The report said more studies will be needed before the wreck can be positively identified.

The Planter, built in 1860, wrecked when a storm came up as it was trying to tow a grounded schooner back to sea at Cape Romain. In the following days, many items on board were salvaged.

"We're not sure how much was left of the Planter because contemporary accounts indicate it was pretty well stripped down all the way to the and blankets and doors," Terrell said. "It looks like the engines and the paddlewheels were taken out."

The items buried in the sand could be the because they would have been corroded by the salt water and not much good for salvage after the Planter sank, Terrell added.

Smalls was born in the Beaufort area and became a river pilot in Charleston in the 1850s. He was later conscripted by the Confederates to serve as a pilot on the Planter.

Smalls took the Planter early on the morning of May 13, 1862, after the Confederate officers aboard left the ship for a night in town.

He steamed upriver to pick up family and friends, then turned around and slipped past five Southern batteries on Charleston Harbor to reach Union blockade ships