Investigators say four teenagers — a 14-year-old, two 15-year-olds and a 17-year-old — are in police custody in a brutal gang rape case that allegedly took place in Brooklyn Thursday night as an 18-year-old victim walked through a park with her father. Those suspects are still being questioned, according to police, and the NYPD is still looking for one other suspect in the case.

The 14-year-old and one of the 15-year-olds were turned over to police by their parents on Sunday. The other 15-year-old and the 17-year-old were apprehended by police later.

Police released surveillance video from Thursday on Saturday night. Investigators say one of the suspects had a gun when the group approached the father and his daughter in Osborn Park in Brownsville.

The suspects demanded the father leave, he returned with two police officers, but the suspects had already each raped his daughter and run away.

The brutal nature of the crime prompted Mayor Bill de Blasio to issue a statement on Sunday:

“I am disgusted and deeply saddened by the horrific attack that took place in Brownsville Thursday evening. We will take every step possible to find and swiftly prosecute the assailants of this vicious crime.

People in the neighborhood say while the park can be dangerous but they're surprised to hear of this kind of crime.

"We don't really hear stuff like that and it's scary to know that five guys did that to a young girl, and it's pretty scary for myself too because I'm right around her age as well," said one.

"It shouldn't happen out here," said another." Too many police officers are out here so I don't know why it happened out here."

"It needs to be police lighting in this park when it gets dark so if anything happens in here, the people walking by can see," said a third. Because, right now it's pitch black and you can't see anything that's going on."

The woman was treated at Kings County Hospital and released.

Anyone with information on the case should contact the Crime Stoppers hotline at 1-800-577-TIPS, or text CRIMES and then enter TIP577, or visit www.nypdcrimestoppers.com.