Several media reporters wrote on Twitter on Thursday that this was one of the worst weeks in journalism, and it’s hard to argue with them. BusinessWeek is canning a third of its staff as Bloomberg gets ready to buy the magazine. The Associated Press is laying off 90 people as part of its effort to cut payroll costs by 10 percent this year.

And now The Washington Post is laying off staff, sources told me on Friday, and a spokeswoman confirmed.

The Post has cut an unknown number of washingtonpost.com workers, the website folks who until now have worked separately at the dot-com headquarters in Arlington, Virginia, across the river from the Post’s headquarters in Washington, D.C. One source told me up to 10 are going. That’s not as big a number as other places you’ve read about lately, but it’s still a painful cut. (Disclosure: I worked for The Washington Post Co. from 1998 to 2005)

Sources shared several names with me, but until those people confirm that they were laid off, I don’t want to publish them. What I can say is that there were several journalists and marketing people among the casualties. They are getting severance packages, but they are accompanied by non-disclosure agreements which prevent them from discussing their firings. Apparently, some of my sources said, they will be out of work by Dec. 31.

Why is this happening? Here’s what spokeswoman Kris Coratti said:

As part of the work we’re doing to turn around the business that supports our journalism, there were a small number of individual positions eliminated as a result of efficiencies we have found through our new structure and through new technology, and those have taken place in both print and online.

The background: The Post’s web staff, as I mentioned, is joining the main newsroom as they eliminate the gap that the paper set up many years ago by making its website a separate operation. The company, all my sources tell me, want to cut staff before the end of the year because next year the remainder would become unionized. Web staff are not unionized now. That, my sources say, would make it much more difficult for the money-losing Washington Post to cut costs by laying off people because they would be protected to some extent by their contract.

With yet layoffs taking place at U.S. media outlets from Conde Nast to BusinessWeek to Time Inc., and advertising revenue showing little sign of rising anytime soon, I have a feeling that we’ll continue to read grim entries like this one.