A teacher walking to work Friday morning was grabbed off a residential street by a drunken off-duty police officer, who walked her several blocks into an apartment building's deserted backyard and raped her, authorities said.

Officer Michael Pena was swiftly arrested by responding officers after a witness who lives in the upper Manhattan building saw through her window that something was happening in the backyard and called 911, police said.

Pena is an officer in the New York Police Department's 33rd Precinct in Washington Heights, south of the Inwood neighborhood, where he's accused of raping the woman. He was being held Friday pending an arraignment on charges of forcible rape and was suspended without pay, chief police spokesman Paul Browne said. He couldn't be reached for comment because he was jailed, and it was unclear if he had an attorney. A call to a telephone number believed to be his home rang unanswered.

Earlier this summer, two NYPD officers were acquitted of charges they raped a drunken woman they had been summoned to help get out of a cab. The officers were convicted of official misconduct for repeatedly returning to the woman's apartment while telling dispatchers they were elsewhere.

The police department fired the two officers within hours of the May verdict, which ignited criticism from women's rights activists and some city councilwomen who said it spotlighted what they considered unfair attitudes toward women who bring sexual assault complaints.

Pena approached the teacher shortly before 6:30 a.m. Friday as she walked to work, asking her for directions to the No. 1 train, Browne said. She could tell he was drunk, and he grabbed her, opened his jacket, showed her a gun and said, "You're coming with me," according to police.

Pena walked the 25-year-old woman several blocks before stopping at the backyard, police said. The woman told police she knew he was armed didn't know he was an officer.

A passer-by walked through the backyard but, perhaps not realizing the woman was being raped, left without helping, police said.

Responding officers from the 34th Precinct arrived about a minute later. Pena and the woman were standing, and the woman ran to the officers, warning them Pena had a gun, Browne said.

The officers took Pena to the ground and realized he was a colleague when they checked for identification and came up with his police ID and shield, Browne said. A loaded handgun was found at the scene. Emergency services responded and took the woman to a hospital.

Pena, 27, has been on the police force since 2008, assigned to the 33rd Precinct since January.

He wasn't working Thursday evening and wasn't expected back to work until late Friday for the midnight shift. It's unclear whether he was carrying his service weapon or his off-duty weapon, police said.