A man has pleaded not guilty to charges he gunned down an imam and his assistant as they left a New York City mosque.

Thirty-six-year-old Oscar Morel entered the pleas on Thursday to charges of first-degree murder, second-degree murder and criminal possession of a weapon in the Aug. 13 attack.

Prosecutors say Morel approached 55-year-old Imam Maulana Alauddin Akonjee and 64-year-old Thara Miah from behind and shot both of them in the head near a mosque in Queens.

Defense attorney Michael Schwed questioned how authorities have handled the investigation, saying witnesses couldn't identify Morel in a lineup. Schwed says he's confident he can prove his client is innocent.