A sizable amount of publishers were removed from Google News without warning late Sunday, the result of what the tech company is calling an unintentional glitch.

"Our news website was removed from Google News and our team is depressed," one publisher wrote on Google's Help Forum. "Help."

"I have been a Google News source for 10 years," another wrote. "This afternoon, all of a sudden, my posts stopped going into Google News."

It's unclear what caused the purge, but it appears to be temporary.

Maricia Scott, engineering director at Google News, says the issue was the result of "an unintentional technical error."

This is "not something we did manually," Scott says. "We are working hard to identify the sites that were incorrectly affected and will get them back as soon as we possibly can."

Some sites are already back online, while insiders at Google tell Ad Age the issue should be resolved by the end of the day.

Still, it's certainly eye-opening how much publishers rely on Google for traffic, with some forum posters claiming they reach "millions of users each month." The issue also doesn't seem to be related to quality, as a decent chunk of reputable publications posted to the forum.

The issue first surfaced late yesterday and has continued on throughout Monday. Publishers were able to determine they were removed after seeing they were no longer "approved."