There's a new warning about deceptive thieves, robbing elderly victims on their own doorsteps. Video from a Ring doorbell captured a scam artist in action, taking $10,000 from Barbara McCullough. It started with a call from someone claiming to be her grandson.
 
"I said to him him, 'It doesn't sound like you.' He said 'I have a horrible cold,' and then he started crying," McCullough said.

The caller said he needed bail money fast.

"I went down to the bank and withdrew $10,000," McCullough said.

What's unusual is the scammer was caught on camera. Grandparent scams are one of the fastest growing crimes and they all begin with a cry for help. Nationwide, seniors are cheated out of nearly $3 billion a year, according to the U.S. Senate Special Committee on Aging.

"I've heard upwards of $10 billion every single year because a lot of these crimes aren't reported. Because a lot of times, they're very ashamed," said Sgt. Dan Suttles. 

A former conman in federal custody provided chilling details about his scam to CBS News in an interview in 2014.

"Once you get them emotionally involved, then they'll do anything for you," he said.
 
As for McCullough, she said she heard someone calling and felt "flattered" that he called her. 

"He didn't want to upset his parents. That's what I thought," she said.

Detectives are trying to track down that scam artist. Officials said seniors can verify who is calling by asking a personal question only the family member would know and by making a call to a relative before handing over any money.