Diane Palmer(HONOLULU, Hawaii) — A Navy corpsman’s mom hopes her missing son is still alive after he vanished following a night on the town with a few Marine buddies, taking in a state fair and having drinks at a popular bar, ABC News has learned.

Seaman Shaun Palmer, 24, who is assigned to the Marine Corps Base in Hawaii, was last seen at Kelley O’Neil’s around 4 a.m. Sunday. He ordered and then canceled two rideshare pickups on his mobile phone — and hasn’t been heard from since.

“I’m praying he’s just really sick or maybe he got beaten up and his phone broke down and he’s hurting but safe,” his mom, Diane, told ABC News.

Diane said she’s heading to Hawaii on Wednesday and hopes to inspire a massive search to track down her one and only child.

“We need to get search parties out in Hawaii,” she said. “What are we waiting for? We need to find my kid!”

 A statement provided by a Hawaii-based Marine Corps spokesman confirmed that there is a dedicated search underway to locate the missing sailor, whose case for now is classified as an “unauthorized absence.”

“Seaman Palmer’s command is coordinating with NCIS and local authorities to find the missing sailor. The safety of our sailors and Marines is our primary concern and we hope and pray for his safe return,” the statement said.

Palmer is a corpsman assigned to 1st Battalion, 3rd Marine Regiment at Marine Corps Base Hawaii, according to a separate statement.

His mother said that while her son wasn’t under any strict curfew to be back at base Sunday night, ABC News has learned that he was supposed to be at an aid station at 8 a.m.

When he was a no-show, Diane said she then received a phone call around 4 a.m. on Monday morning by military personnel who identified themselves as members of the Naval Criminal Investigative Service.

“They wanted to know if I’d heard from him,” said the mother, who said she hasn’t slept since the phone call. “But Shaun was already missing for 24 hours.”

Diane said that she learned that Palmer and two Marines spent Sunday visiting a state fair.

She knows this because she caught a post her son, a native of Iowa, left on his SnapChat account that she said included a typed message reading: “Someone say state fair?” as he made a “funny face,” Diane said.

The three servicemen then made their way to Kelley O’Neil’s bar, a popular military hangout known for live music.

The mother, who has spoken with NCIS investigators as well as Honolulu Police Department detectives, said that she learned that Palmer was at the bar until around 4 a.m.

One of the Marines returned to base.

Palmer and the unidentified friend remained until the bar’s closing.

According to a bartender working that night, it was “packed” at the bar but nothing was out of sorts.

“There was no indication that anything was out of the ordinary,” the bartender, who said he’s worked at the establishment for nine years and spoke to ABC News on the condition of anonymity, said. “It was a typical closing.”

The bartender noted that there was a heavy presence of local cops nearby and that a day ago, the staff searched surveillance footage from that night after being prompted to do so by NCIS investigators.

“We looked at the cameras and didn’t find anything,” the bartender said. “I can tell you that nothing happened inside the bar.”

While the bar was cleared out and people spilled out in the street, Palmer’s friend was subsequently arrested for “a low-key disorderly conduct,” his mother said. She’s still trying to learn the identity of the arrested Marine.

Attempts by ABC News to speak with Honolulu Police Department about the arrest of the unidentified Marine or the case involving Palmer were not immediately successful.

A detective with the department refused to share any details about the Marine’s arrest or Palmer’s missing case, saying, “it’s an ongoing investigation.”

Diane said that she learned from NCIS investigators that her son then summoned two different Lyft cars.

“My son ordered the Lyft to go back to base,” Diane said. “It was canceled.”

She was then told her son then was three blocks away and ordered a second Lyft, which also was canceled, a fact confirmed by her conversations with detectives and her son’s bank records.

“He canceled the second one, and it’s on his bank account at 4:28,” she said, referring to the morning time stamp.

She said that afterward Palmer’s cell phone “went dead.”

All Diane can do is hope.

“We’re very close,” she said. “We’ve always been like that. And I know his heart is breaking for my heart. I just know it.”

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