DENVER -- If your cell phone falls into the wrong hands it can be surprisingly easy for someone to drain thousands of dollars from your bank account.

A stolen cell phone cost Taiya Andrews $12,000 and countless hours of fighting with her bank to get the money back. She was at a bar when a person bumped into her and even though her phone was in her closed purse she believes that's when someone took it.

"It can definitely snowball into a whole bigger thing than you ever thought," said Andrews.

Denver police detectives have seen at least 11 similar cases where phones were stolen in crowded places to gain access to bank accounts.

"This was something new to us," said Sgt. Timothy Blair with the Denver Police Department. He continued, "It's just like losing your credit card."

Popular banking and money transfer apps could be leaving your bank account vulnerable, enabling criminals to drain your funds in a matter seconds. Police wouldn't name specific apps but say if you can easily transfer money to your friends it's just as easy for the bad guys to transfer it to themselves.

"They like to steal a couple of phones and they can move the money back and forth and then the money can be off loaded to another account," said Sgt. Blair.

Police saw a waive of similar crimes over the summer where total losses were right around $3,000 per transfer. In many cases they say it's difficult to track these thieves down and even more difficult to recover the money.

Denver police offer the following tips for protecting your cell phone:

Make sure your bank account or money transfer app has a secondary sign in and that it has a different password than your phone's lock screen.

Use a fingerprint ID to unlock your phone and for your apps. Do not have your passwords automatically saved in the phone.

Keep your phone software updated.

Always keep your phone on you and avoid setting it down on a table unlocked.

If your phone goes missing call police and your wireless carrier. Also notify your bank if you think the thieves might have access to the account.

When Andrews' phone was stolen she thought the criminals would be more interested in the device; as it turns out, they just wanted access to the information on it. Her stolen phone was used to call her boyfriend, the person on the other line said he was the manager at the bar where she lost her phone.

"I spoke with this person on the phone... he gave his name, a name, he introduced himself like that was definitely an uneasy feeling," said Andrews.

She said the man asked for her password in order to verify that it was her phone. In her haste to get her phone back she gave them her pass code, never stopping to think the man could have been lying.

"Even that day after I gave him the pass code I didn't really think even then that they we’re going to get into my bank account and my thought was, 'yeah, they’re going to resell this,'" said Andrews.

Police said they've also seen instances where criminals are successfully able to get into locked phones and steal money.

"If somebody gets your phone they may have access to your bank and if it’s someone who knows what they’re doing they can get to it pretty quickly," said Sgt. Blair.