MADISON, Wis. (WISC) -- State elections officials responded to a report from NBC Nightly News alleging that seven states -- including Wisconsin -- were successfully compromised prior to the 2016 election.

The report suggests that while the federal government had substantial evidence that state websites or voter registration systems in seven states were affected by Russian-backed covert operatives, they never told the states involved. These states include Alaska, Arizona, California, Florida, Illinois, Texas and Wisconsin.

The list of states comes from a top-secret intelligence request by former President Barack Obama during his last weeks in office, according to NBC News. The results from the request are dated January 2017.

Eight months later, in September of 2017, the Department of Homeland Security informed 21 states, including Wisconsin, that they had been targeted by Russian operatives. At the time, federal officials acknowledged that a number of the attempts were successful, but did not list in which states.

After the announcement, there was some confusion among Wisconsin officials as to the nature of the incident. In the end, the state election commission believed that while there was no breach of data, Russian hackers had scanned Wisconsin's internet-connected election equipment.

Intelligence officials cited in the NBC News report said the government had to use "exceptionally sensitive sources and methods," including human spies and eavesdropping on Russian communications in order to confirm that the Russian government was behind the hack.

The NBC News report said several state election officials believed they should have been informed that their systems had been breached, if the hack was indeed successful. Federal officials told NBC News that the reluctance to share the information, is partially because it was classified intelligence and none of the state election officials had the appropriate clearance.

Wisconsin election officials said in a statement Tuesday that the DHS has not informed them of any new hacking attempts since September either successful or unsuccessful.

“The Wisconsin Elections Commission has never detected a successful hacking attempt on its systems, nor has it ever been notified of one by the Department of Homeland Security or any other state or federal agency," Wisconsin's chief election official Michael Haas said in the release. "We are not aware of any new Russian targeting of Wisconsin systems beyond the scanning attempts from 2016 we reported in September 2017 as soon as we were notified by DHS.”

Haas added Tuesday that the Wisconsin Elections Commission believes the DHS when they say their systems are secure.

"We have established a strong, positive relationship with Homeland Security, and have seen no reason to doubt their assurances about the integrity of our systems," Haas said in the statement.

If the hack was successful, both state and federal officials said in the NBC News report that there is a sense of urgency to resolve any security concerns before the 2018 election. Some believe, that because state agencies were not informed sooner, this won't be possible.

Haas said Tuesday in the statement he does not believe there is a reason to be concerned about the security of Wisconsin's voting systems, saying, "Wisconsin’s voter registration system and voting systems are secure."