From left: Evgeniy Bogachev, Nicolae Popescu, Alexsey Belan, Peteris Sahurovs and Shaileshkumar Jain, the FBI's top 5 most wanted hackers. (Mugshots via FBI)

These aren't the murderers, drug traffickers and rapists who usually are on the FBI's lists, but cyber criminals are still some of agency's most-wanted bad guys.

The top five most-wanted cyber criminals, based on the amount of money offered for their capture and prosecution, are responsible for hundreds of millions of dollars in losses, according to FBI statistics, and authorities are willing to pay a combined $4.2 million for information leading to their arrest.

Online crime has increasingly become a sticking point for the Obama administration as large companies, from Target to Sony, and government agencies, like the Office of Personnel Management, have fallen victim to hackers.

[OPM still isn’t saying how many people were caught up in its breaches]

The five hackers being targeted by the FBI are accused of stealing health, employment, and banking data, or trying to force people to pay a ransom to regain control of their devices and running fake online auctions.

Here's the rap sheet for the FBI's five most-wanted hackers:

1. Evgeniy Mikhailovich Bogachev | Reward: $3 million 

Bogachev is the mastermind of ZeuS, a trojan horse that steals bank account numbers, passwords, security questions -- any information that could be used to seize control of a bank account. ZeuS hackers used that information to pose as administrators on those accounts and transfer funds in ways that don't raise red flags for banks. He's responsible for $100 million stolen from banks since 2009, when the FBI began investigating ZeuS, said Special Agent Christopher Stangl, who heads the Computer Intrusion Section of the FBI’s Cyber Division.

And even though the FBI says it wants all criminals equally, Bogachev, who is thought to be in Russia, still tops agents' list.

"He’s probably our number 1 target," said Stangl.

2. Nicolae Popescu | Reward: $1 million

Popescu used a "tried and true" method of bilking online consumers, Stangl said. He set up fake auctions for automobiles on sites, such as Cars.com and AutoTrader in 2012, purporting to sell cars that just didn't exist. Popescu and other hackers affiliated with the scheme made $3 million off the auctions. And though six members of the ring were arrested in 2012, authorities did not apprehend Popescu, who the FBI believes is in Romania.

3. Alexsey Belan | Reward: $100,000

Belan stole consumer data in 2012 and 2013 from three e-commerce sites in Nevada and California, sites the FBI declined to name. He's now selling that data to other criminals, Stangl said.

"This information is extremely valuable in the underground market, and that market drives the bad guys that commit those crimes," said Stangl.

4. Peteris Sahurovs | Reward: $50,000

Posing as a fake hotel chain, Sahurovs sold ads laced with malware to news Web sites. When users reached the page where the ad was displayed, the malware locked the computer and encrypted its files, demanding a $50 ransom to regain functionality. If the ransom wasn't paid, the computer would be flooded with pop-ups.

Hackers keep the cost relatively low on these operations so people would pay the ransom, Stangl said. That's a lot easier, sometimes, than going through law enforcement or computer repair shops to find the source code for the malware.

Sahurovs, a native of Latvia, made $2 million using this hack.

5. Shaileshkumar "Sam" Jain | Reward: $50,000

Jain is the only American citizen on the list. He made $100 million between 2006 and 2008, according to the FBI, by using a flood of pop-up ads to convince users their computers were infected with a virus. Then he sold users bogus software, or "scareware," said Stangl, to get rid of the pop ups.