A hand grenade was found on Pagham beach by a person with a metal detector on Thursday (November 14).
According to Selsey Coastguard Rescue Team, it took more than 24 hours to remove the grenade from the beach.
Its post on Facebook read: "Team paged after a hand grenade had been found on the beach in Pagham by a person with a metal detector.
"Sussex Police were initially called, and on scene before they handed it over to the Coastguard to deal with.
"The police had filled some sandbags and surrounded the item with them to try and protect it from the incoming tide.
"Unfortunately E.O.D. (Explosive Ordnance Disposal Team) were unable to attend before the tide covered it. We stayed on scene until it was fully covered by water and were then stood down."
The team were re-tasked early on Friday morning to return to the beach, when the tide was low.
"Once again the beach was closed to the public," the post added.
"Due to the position of where the grenade was on the low tide mark, we had a very short time frame for E.O.D. to deal with the ordnance.
"We confirmed the sand bags were still in place but unfortunate the tide covered it again before E.O.D. arrived. So once it was safely covered by water the team were stood down."
The team again returned to the beach at 4.30pm on Friday.
The post continued: "The beach was again closed and we confirmed once the tide was low enough that the sandbags were still in place and E.O.D. were again tasked.
"E.O.D. arrived on scene and confirmed the grenade to be a Mills grenade. The beach was reopened later and both E.O.D. and ourselves were stood down, returning to station at 8pm."
Selsey Coastguard Rescue Team also issued a warning to beach-goers.
"If you ever come across a grenade or any ordnance on the beach, please do not touch it and dial 999 and ask for the Coastguard straight away," it said.
"Ordnance comes in all shapes and sizes and can still be extremely dangerous and highly explosive. Do not touch it and call the Coastguard.
"In an emergency out at sea, on the beach or along the coast dial 999 and ask for the Coastguard."