They had a beachcombing blast on the coast after old munitions washed ashore

Beachcombing was a blast for soldiers from Joint Base Lewis-McChord earlier this week. An ordnance disposal unit was called out after unexploded military munitions washed up on the beach north of Ocean Shores, Washington.

The Grays Harbor County Sheriff's Office issued a warning to the public after beach goers and deputies found scatterings of decades-old, sludge-encrusted projectiles. Some people were taking their surprising discoveries home as souvenirs, which alarmed the authorities.

"What we've been finding is anti-aircraft high explosive rounds," said Chief Criminal Deputy Kevin Schrader. "They kind of resemble large rifle ammunition."

Schrader figured the munitions date to the 1940s when a naval gunner's school operated on a bluff above the wide, sandy beach in the community of Pacific Beach.

"I think just the strong tides and currents are bringing them to the surface," said Schrader by way of explanation of why the very old, discarded rounds are reemerging now.

The sheriff's office called JBLM for help, as it did a year ago when this happened before. The Army sent out an ordnance disposal unit on Monday.

Army spokesperson Becca Nappi said that soldiers from the 787th Ordnance Company carefully collected all the rounds they could find and then blew it all up at the beach.

"The 27 items were disposed of by conducting one controlled detonation," Nappi said. "There is no cause for concern for anyone near the site. This kind of controlled detonation is something that our Soldiers train for and perform all year-round and is part of what makes them experts in their field."

Schrader said the loud boom on Monday evening was heard as far away as Aberdeen. He said he has heard no reports of injuries to beachcombers who may have picked up potentially unstable rounds earlier.

The Army command and Schrader both reiterated that beach goers should retreat and call dispatch if they find additional rounds. Marking the location at a safe distance is also helpful.

"We're telling people, don't remove them from the beaches," Schrader said in an interview Wednesday. "Don't touch them. Don't move 'em. Don't transport 'em. Give us a call."

After the county sheriff and emergency management departments posted their warnings on Facebook, local residents shared stories of finding military rounds in the sand since they were kids.

"Kinda scary with all the clam digs going on," wrote a Pacific Beach woman.

"What happens when someone builds a fire over one of those, and doesn't know it's under the spot they have chosen?" replied another area woman. "I know of an incident like this that has apparently already occurred."

The former Naval Facility Pacific Beach has a colorful history. The Navy and Air Force took over the property of a beachfront honeymoon hotel with the outbreak of World War II. The facility was used for a radar station and gunner's school. A naval history website said the military mission ended in 1987. The facility remains government property. Having been renovated, it is now used as a resort and campground for active duty and retired service members.