The San Francisco Bay Guardian has ceased operations and will publish its last newspaper tomorrow, according to online reports supported by an internal email at the company and a tweet from the newspaper’s official twitter account.

The announcement was made to employees in an email from Glenn G. Zuehls, publisher of San Francisco Media Co., according to a report first published today by SFist. The Guardian was acquired by the San Francisco Media Co. in 2012 as part of a group that also manages San Francisco Examiner and SF Weekly.

SFBG publisher Marke Bieschke also confirmed the report via his Facebook page:

“The San Francisco Media Corporation has just pulled its funding from the 48-year-old San Francisco Bay Guardian. All operations have ceased for the moment. Unfortunately, tomorrow’s Best of the Bay did not make it online, so you’ll have to instagram it y’all. More details to come.”

The newspaper has a long history of supporting progressive politics in San Francisco but has struggled in recent years to stay profitable as the newspaper industry continues to shrink.

An excerpt from the internal email from Zuehls via SFist:

Unfortunately, the economic reality is such that the Bay Guardian is not a viable business and has not been for many years. When SFMC took over the publication, the company believed the publication’s finances could rise out of the red and benefit from joining forces with the Examiner and the Weekly. We have tried hard to make that happen over the past few years. I joined SFMC in June and was hopeful that I could make good on that potential. I was excited to see if the Guardian could be a part of the long-term stability and growth of this unique media partnership.

Since then, I have come to realize that this isn’t possible and that the obstacles for a profitable Bay Guardian are too great to overcome. The amount of money that the Bay Guardian loses each week is causing damage to the heart of the company and cannot justify its continued publication. The success of this company, providing the highest quality journalism for our readers along with superior results for our advertisers, is my sole priority.

I am a huge fan of the Bay Guardian and of the talented journalists that work here. This is the hardest decision that I have had to make in my 20 year Newspaper career.

However, the closure of the Guardian does not rule out the potential sale of the publication and the newspaper’s editor Steven T. Jones confirmed with SF Weekly that he is exploring options for buying the newspaper if there is support in the community.