Senate emails back up after 'network outage'

Lights illuminate the The U.S. Capitol, which is covered in scaffolding for ongoing restoration of the Capitol dome, in Washington, Wednesday, Jan. 14, 2015.

Washington (CNN)The "network outage" the U.S. Senate faced on Wednesday that brought down emails and websites was largely resolved by Thursday morning, according to the Senate Sergeant-at-Arms.

The roughly 12-hour outage came after a "network router experienced a hardware failure," the Sergeant-at-Arms's office explained in an email to Senate staffers. There was no evidence of any wrongdoing.
The office told staffers that technicians completed repairs early this morning, but are still testing services to ensure they are fully functional.
Four Senate staffers confirmed their emails were down on Wednesday evening and they were having trouble accessing some Senate websites, but they did not know what caused the outage.
    One Senate staffer told CNN that email systems in his office went down at around 5:20 p.m.
    "It seems likely that that's not just some routine maintenance," he said, adding that he had not received any updates from the Sergeant-at-Arms office nor had he heard from the Capitol Hill Police Department.
    At about 9:06 p.m., the Sergeant-at-Arms tweeted that the issue had been identified and engineers were working on a fix.