NEW YORK (PIX11) — Amid a spike in attacks, the NYPD is searching for alleged sexual predators in several instances..

Two attacks took place an hour apart in Manhattan on Saturday. One attack happened around 4 a.m. Saturday on the Upper West Side. Police say a 23-year-old woman was walking near Central Park West and West 82nd Street when she was attacked from behind and sexually assaulted. The perpetrator fled the scene on an e-bike, striking again an hour later.

Police say the second attack happened around Avenue A and East 4th Street. The man reportedly approached a 28-year-old woman on his e-bike, pulled her to the ground, and assaulted her. He is still on the loose. 

Police are investigating a separate sex crime that took place on July 10 in North Corona, Queens. Investigators say a man wearing a cowboy hat and carrying a blue guitar grabbed a 30-year-old woman’s buttocks. The woman followed him as he went into a nearby residential building and changed clothes.

According to the NYPD, sex crimes are up 18.6% so far this year, compared to the same time period last year. Emily Miles, the executive director of the New York City Alliance Against Sexual Assault, said the statistics only tell a small part of the story. 

“The numbers we’re looking at are actually incredibly flawed,” said Miles. “What we’re tracking with those crime stats are survivors who are actually reporting sexual violence to the NYPD. And we know that…70 to 80% of assaults are never reported.”

Miles said that random, violent crimes – like those perpetrated over the weekend – represent just a small percentage of all sex crimes. 

“You are far more likely to be assaulted by someone you know – a friend, an acquaintance, a family member – almost 80% more likely,” said Miles. 

It’s those types of sex crimes that go unreported, said Miles. 

“A majority of cases of sexual violence are not happening in Central Park as someone walks down the street,” Miles said “They’re happening in people’s homes.” 

Submit tips to police by calling Crime Stoppers at 1-800-577-TIPS (8477), visiting crimestoppers.nypdonline.org, downloading the NYPD Crime Stoppers mobile app, or texting 274637 (CRIMES) then entering TIP577. Spanish-speaking callers are asked to dial 1-888-57-PISTA (74782).