Hackers knew about Democratic nominee Hillary Clinton’s private server and tried to hack it 10 times in a two day-period in 2010, and the Secret Service knew about the attempted intrusions, new documents show.

The hackers used the names of top Clinton aides as login names — doug, dougband and huma. The attack showed as coming from OpenDNS, a company that the Clintons’ server used to map domain names to IP addresses, meaning the server relied on and couldn’t block it.

“Might have been an injection attack,” Clinton IT staffer Bryan Pagliano wrote in a Nov. 30, 2010, email to Justin Cooper after the aide received 10 automated emails warning of failed login attempts.

Pagliano then sent the same email to the Secret Service. Pagliano later refused to testify before Congress about Clinton’s server and private emails that were abruptly deleted, invoking the Fifth Amendment.

The emails were among 15,000 Clinton emails discovered by the FBI and released by the Department of State in response to a lawsuit by the conservative nonprofit government watchdog Judicial Watch. The emails are here.

“Would be useful to know if it was them who tried to log in,” Pagliano wrote. “Symantec logged a denial of service attack on the main server which could be a usual occurrence, but I am looking into it. I can’t tell yet if the pix (firewall) is picking this up too, I [am] looking through the logs a bit more, but things are running slow, seems like the internet connection is getting clogged up.”

Pagliano added in the email that “it would be useful to know if the ISP is seeing any denial of service traffic from them across the internet wire if you are able to call them.”

Clinton campaign spokesmen have argued that having the Secret Service guarding the former secretary of state’s New York mansion somehow made the server there secure. Stealing digital information, however, rarely involves physically stealing a computer and the Secret Service does not specialize in information security.

Clinton hired many IT staffers based on personal connections and they have sometimes served her poorly. Her national campaign chairman John Podesta knew to be skeptical of a phishing attempt, but it was a Clinton IT staffer who wrongly told him the highly suspicious email was a legitimate request to enter his password.

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