HOUSTON — As investigators examine two boxes of items seized from Robert Durst’s Houston home, the troubled millionaire’s attorney says he would be surprised if any evidence against his client were found.

Dick DeGuerin called the search of the condominium Tuesday “a publicity stunt” by a California prosecutor looking to pin the killing of Durst’s friend 15 years ago on his client.

But Durst himself may have pointed to his Houston condo, in a recording made while talking to himself in a bathroom immediately after a tense interview with the makers of a documentary about his life.

Just before saying he “killed them all,” he says “I don’t know what’s in the house!”

In this bathroom tape — which forms the shocking conclusion of the six-part HBO documentary that wrapped up Sunday — Durst talks to himself in short bursts of whispers, apparently contemplating his arrest. The filmmakers say they shared the tape with police months ago.

The 71-year-old heir to a New York real estate fortune remains in custody in New Orleans on gun and drug charges while awaiting a transfer to Los Angeles to face murder charges in the death of Susan Berman.

Durst also has been suspected — but never charged — in the disappearance of his first wife in New York. In 2003, he was acquitted of murder in a dismemberment death in Texas.

Seven officers spent hours Tuesday searching Durst’s condominium in a 17-story building in a posh Houston neighborhood before carrying away the two white cardboard document boxes.

“I don’t know what they could be looking for 15 years after Susan Berman was killed 1,500 miles away,” DeGuerin said.