Alleged Gilgo Beach serial killer Rex Heuermann’s defense attorney Michael Brown is demanding information about someone he says was a past “top suspect,” according to a letter obtained by News 12.

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According to the letter, a person with the initials ‘WH’ is the other potential suspect. The letter states that ‘WH’ was a police officer, and Brown claims that person also lives in Massapequa Park.

As News 12 has reported, a belt with the letters ‘WH’ or ‘HM’ on it was found on victim Maureen Brainard Barnes' body.

The district attorney has confirmed to News 12 that there are ancestors of Rex Heuermann’s with the initials ‘WH’ as well.