Latino rights group Respect Respeto sent a letter on Monday to the Justice Department asking for a probe into allegations that Sheriff Paul Babeu threatened a Mexican immigrant ex-lover.

The organization said the allegations, if proven true, may constitute an abuse of power as an elected official. 

The Pinal County sheriff, who is running for the GOP nomination for a congressional seat, resigned as Arizona co-chair of the Mitt Romney presidential campaign Saturday, after the Phoenix New Times reported a story alleging Babeu had threatened a Mexican immigrant ex-boyfriend with deportation if he made their relationship public. 

Celebrities Who Were Once Undocumented

Babeu denies the allegations, but the story prompted him to confirm publicly that he is gay -- a development that may wind up damaging his reputation among his conservative base

KNXV-TV reports Respect Respeto wants the sheriff investigated on behalf of every immigrant who has been threatened with deportation.

The group alleges in its request to the Justice Department that Babeu made "text messages, pictures and threats that are unbecoming of an elected sheriff."

Based on reporting by the Associated Press.

Follow us on twitter.com/foxnewslatino
Like us at facebook.com/foxnewslatino