NEW YORK (CBSNewYork) — You could be a victim and not even know it, thanks to something known as ‘upskirting.’

“It’s sick and annoying and something else a woman has to think about while going to work,” Maggie Tang told CBS2’s Ali Bauman.

The act of taking pictures up a woman’s skirt is a felony called ‘upskirting.’ When hemlines rise with the temperature, so do upskirting arrests. There were five in New York City during an unseasonably warm week in March.

Yanco Alvarez was arrested at the 8th Ave and 14th Street station for using his phone to record up a woman’s skirt while walking behind her.

It turns out your smart phone isn’t the only device that can secretly record.

“Cameras can be built into just about anything now, so if you’re looking at anything you need to realize there could possibly be a camera in it,” Spy Shop, Sales Manager, Anthony Klusser said.

The Spy Shop in Murray Hill installs security cameras in car keys, watches, even DVDs. The gear starts at about $200 and is easy to overlook.

“The pen is very popular because you can hold it in your hand. The camera’s right here,” Klusser said.

The devices are meant to protect people, but the store admits they can be misused.

“We had a customer come in, said he did hotel security. He brought a backpack in, he wanted a custom built camera. Turns out her was using it for upskirting. He came back and had the audacity to tell us what he was doing,” Klusser said.

The district attorney’s office said if you see something say something, but the problem is it’s hard to spot and women admit it’s hard to prevent.

“It’s why I wear spanx everyday. It helps protect against something like that,” Tang said.

“When you’re walking up and down the stairs put your dress behind you, be a lady about it,” Nicole Melendez said.

Upskirting is punishable with up to four years in prison, and a potential sex offender registration.

If an image is shared online, the perpetrator could also be charged with a second felony crime.