BOSTON (AP) – Prosecutors have charged a man with assault with intent to rape, a day after he was rearrested after walking free when police allowed him to go unsupervised to the hospital.

Edwardo Aponte, 29, pleaded not guilty at his arraignment on charges that also include indecent assault and battery stemming from a September 5th incident in which he allegedly sexually assaulted a woman in a Chinatown alley. He was arrested after the woman identified him as her attacker.

Aponte was being held at a South End police station when police say he reported feeling sick Sunday morning. He was taken, unaccompanied, by ambulance to New England Medical Center. Police said he apparently walked away from the hospital.

Aponte was ordered held on $250,000 cash bail and will return to court October 12th.