The Internal Revenue Service revealed Monday that there were as many as 330,000 taxpayers' accounts that were hacked by identity thieves, twice as much as what was first reported.

According to the IRS, the cyber crooks hacked through the system using Social Security numbers and other data to get information on prior-year tax returns.

In May, the IRS reported that the hackers gained access to 114,000 accounts and was unsuccessful in penetrating 111,000 other accounts. But just this Monday, IRS revealed that the numbers are twice as much as that at 330,000 successful hacks, and 280,000 unsuccessful ones.

The hackers were able to slither through multistep authentication processes by using Social Security numbers, street addresses, birth dates, and other personal information. They used the information to file fraudulent returns and made almost $50 million in refunds.

The cyber attackers got the information from "Get Transcript" online application, which lets taxpayers call up information from previous returns. After the May attacks, this system was shut down. According to the IRS, "some of this information may have been gathered for potentially filing fraudulent tax returns during the upcoming 2016 filing season."

IRS said it will soon mail letters in the next few days to inform the taxpayers that whose accounts were hacked. They will be given free credit monitoring nd a new personal identification number to verify the authenticity of their tax returns next year.

This new revelation will be another controversy added to the problematic public-relations of the agency. According to the Senate Finance Committee Chairman Orrin Hatch, the inability of the agency to block these cyber attacks may lead to further fraud on the "hardworking taxpayers."

How the IRS disclosed the real story is becoming a trend among hacked Federal agencies. They first give a smaller number, and later on give the real staggering figure of accounts hacked.