Barack Obama
© AFP Photo/Jewel SamadUS President Barack Obama.
The long-form birth certificate released by the White House in April 2011 is fraudulent, claim investigators acting as a posse for Arizona's Maricopa County Sheriff Joe Arpaio.

The posse had earlier said the certificate may have been a computer-generated forgery, but now they say they are positive that the document is a fake.

Mike Zullo, the posse's chief investigator, said numeric codes on certain parts of the birth certificate indicate that those parts were not filled out. He added that those sections asking for the race of Obama's father and his field of work or study were completed.

Zullo said investigators previously did not know the meaning of the codes, but they were explained by a 95-year-old former state worker who signed the president's birth certificate.

So-called "birthers" believe that President Barack Obama is not eligible to hold America's highest office because he was allegedly born in Kenya, not Hawaii, and thus is not a natural US citizen.

Obama Birth Cert
© AFP Photo/HO/The White House
Hawaiian officials have repeatedly confirmed Obama's citizenship, state officials reiterated on Tuesday.

"President Obama was born in Honolulu and his birth certificate is valid," Joshua A. Wisch, a special assistant to Hawaii's attorney general, said in a statement. "Regarding the latest allegations from a sheriff in Arizona, they are untrue, misinformed, and misconstrue Hawaii law."

The Arizona Democratic Party says Arpaio's probe into the issue is aimed to draw attention away from the problems in his own agency, including hundreds of sex-crime cases that the sheriff's office failed to adequately investigate over a three-year period.

Obama's office released a copy of his long-form birth certificate in an attempt to quell citizenship questions, but it is still being debated by some of his opponents.