A Washington Heights man was arrested in the sexual assault of a woman outside a neighborhood church, authorities said.

Police tracked down Xavier Lazu, 20 — who lives only about two blocks from the crime scene — through tips from the public, cops said.

Lazu allegedly ran up behind the 23-year-old victim in front of St. Rose of Lima Church on West 165th Street near St. Nicholas Avenue around 11:20 p.m. Monday, wrapped his arms around her and put his hand over her mouth, police said.

Then he dragged the woman under a nearby awning — telling her not to scream or he’d stab her, cops said.

The assailant shoved her against a wall, pulled her pants down and tried to rape her, authorities said. When he was unable to, the sicko forced her to perform oral sex on him — and then took off when someone walked by.

The victim was taken to a local hospital for an evaluation.

Lazu was charged with attempted rape, criminal sex act and sex abuse, cops said.

He has no prior arrests.