(NEWSER) – An HIV-positive Missouri man now has more to fear than romantic rejection. Police allege that David Lee Mangum has exposed some 300 sexual partners to HIV in the last decade, which is how long he has known he's had HIV. They say the 37-year-old told them as much during their interview with him, reports the Daily Statesman. Mangum was arrested Aug. 28 after a former partner, identified only as DB, contacted police. DB says Mangum told him he had no STDs, but that after the two broke up in June he received a phone call from Magnum's old roommate, who alerted him to Magnum's condition. DB's HIV test came back positive.