Girl Found Dead on Long Island Street on Eve of Her 16th Birthday, Body Believed to Be Best Friend's Recovered Nearby: Police

Two teenage girls were found dead less than a day apart on Long Island, hours after they were hanging out together Tuesday evening, police say.

Nisa Mickens was found beaten to death on Stahley Street in Brentwood Tuesday night, the eve of her 16th birthday, according to police. A passing motorist found the body and called police. 

Mickens was found brutally beaten with at least 10 injuries, including cuts and head trauma, police officials said. She was pronunced dead at the scene, and a medical examiner later ruled that she died in a homicidal assault. 

Her best friend, 16-year-old Kayla Cuevas, had been with Mickens earlier in the day and was reported missing after Mickens was found. Twenty hours later, police said they found a body matching Cuevas' description in a wooded area just a few hundred feet from where her friend's body was. A neighbor had called 911 to report the body near a tree in their yard.

Suffolk County Police Det. Lt. Kevin Beyrer said investigators believe the two killings are connected, though they're not offering a possible motive. They say the deaths may be gang-related. 

"This brutal attack of a teenager will not stand in Suffolk County," Police Commissioner Tim Sini said. "We're going to catch this depraved perpetrator."

It's not yet clear how Cuevas died.

The mothers of the girls held each other Wednesday night on the roadway where Mickens' body was found. They grieved their daughters under the pouring rain. 

"We're all out here for our babies," said Elizabeth Alvarado, Mickens' mother. "It has to stop. The killings are going to stop. What's it going to take?" 

NOW - grieving mother leaves flowers and balloons at the spot her 16yo daughter was found dead. "This is senseless! No one should bury their child!" Mom begging for someone to come forward with information. Suffolk Co Police homicide investigating the death here in Brentwood, LI. #nbc4ny

A photo posted by Marc Santia (@marcsantia4ny) on Sep 14, 2016 at 9:47am PDT

As thunder clapped, Alvarado said, "She's crying over us. She's washing everyone's sins away."

On what would have been Mickens' birthday, her parents left the gifts she'd asked for, a basketball and balloons, on the spot where her body was found. 

Anyone with information on her death should call Crime Stoppers at 1-800-220-TIPS.