NEIGHBORS of be­loved “M*A*S*H” star GARY BURGHOFF – who played Ra­dar O’Reilly on the hit ’70s show – fear that the publicity-shy star is suffering from mental decline, boozing and on a frightening down­ward spiral!

Sadly, the 70-year-old former actor is living as a virtual shut-in in a Florida RV park, and pals there are praying he gets help before it’s too late.

“Gary is starting to show early signs of dementia,” said a source. “He’s also drinking excessively and taking large amounts of Valium.

“Gary is getting more and more forgetful. He’s more agi­tated and gets angry over little stuff that never bothered him before.

“It’s a small community, so we all would just drop by to say hello or to chit-chat out­side while smoking a cigarette or drinking a beer. But lately, if you drop by his place, Gary gets angry and tells you to go away. He’s never been that way until lately.”

In March, The ENQUIRER reported that Burghoff had moved to Nature Coast Land­ings, an RV park in Crystal River, Fla., near the Gulf of Mexico, where he loves to fish, ride his motorized bike and walk his dog through nature paths.

But things have changed over the past few months.

“Gary will not allow any of his old friends to visit him like he used to,” said the worried pal, who added that the former TV star’s RV is now filthy.

Burghoff, who is twice di­vorced and has three children, also owns a home in Connecti­cut. But he’s always preferred his life on the road in his RV.

In late November, an ENQUIRER reporter witnessed two of Burg­hoff ’s neighbors drop bags of groceries at his front door after he refused to let them in. When the neighbors left, he scooped up the groceries and hurried back inside.

Later that day, Burghoff re­fused to answer his door for The ENQUIRER reporter but agreed to speak over the phone.

“If I open my home to you for an interview then it opens the floodgates for other people to start contacting me, asking for interviews as well – and the publicity is just not something I want in my life anymore,” Burg­hoff explained. “I’ve finally reached a place in life where people don’t recognize me or bother me because of that TV persona that I used to have, and I’m trying to do everything I can to preserve my peaceful life.

“I consider any fans I might have left my friends, and as my friends they should respect my privacy and find happiness in knowing that I’m happy, healthy, enjoying a peaceful life of retirement.”

Despite his words, Burghoff ’s friends aren’t convinced. They hope his family steps in to get him the help he needs before it’s too late.

“We love Gary and know he is not being himself,” the friend add­ed. “Something is terribly wrong.”