A video released by a Sunset Park community group shows a visibly pregnant woman crashing belly-first to the street during an arrest, and officers kneeling on her as she lies face-down on the pavement. The video was captured on Fifth Avenue shortly after 2 a.m. on Saturday. Sandra Amezquita, a 44-year-old Colombian immigrant, says she tried to intervene when officers allegedly beat her 17-year-old son.

The video appears to show Amezquita, who is five months pregnant, resisting arrest and then toppling face-down to the street as an officer tries to handcuff her. As she lies on the pavement, two officers are seen on top of her as they effect the arrest. Another unidentified woman who tries to interfere is also shoved to the street.

The clash with police erupted after officers say they found a knife on Amezquita's son Jhohan Lemos during a routine stop-and-frisk. He was charged with criminal possession of a weapon, resisting arrest and harassment. A photo of Lemos taken after the arrest shows his face scarred with multiple bruises, and one of his eyes swollen shut.

Amezquita's husband, Ronel Lemos, was also arrested; police say he punched one of the officers in the back as they were making arrests.

"What we saw in that gruesome video is a woman who's trying to protect her son, who is being stopped and frisked by police, and she herself became a victim, slammed onto the floor," Dennis Flores, of the community group El Grito de Sunset Park, tells ABC 7. "Her belly is now with black-and-blue bruises."

Amezquita tells the Daily News, "You would think the police would respect a woman that is pregnant. I was afraid something happened to my baby. I am still afraid that something is wrong." She experienced vaginal bleeding following her arrest, and continues to experience abdominal pain.

"This is the second video in a week," Councilmember Carlos Menchaca said, referring to another alleged incident of police brutality at a Sunset Park street fair. "This is disturbing. Yet again, we are seeing this kind of aggressive tension from the police and the community. This needs to stop."

Internal Affairs is investigating Saturday morning's incident and the street fair melee, both of which involved officers from the 72nd Precinct.

High profile lawyer Sanford Rubenstein is now representing Amezquita and her husband. "What happened is appalling and should not be happening in New York City,” Rubenstein tells PIX 11. “These videos are pictures of the truth and those who take them are performing a public service."