It's becoming increasingly apparent that Twitter is playing an important role in getting news out of Iran.

For those who use that site, the #tag for posts and searches has been #IranElection. (To the uninitiated, a # mark followed by a search term is a way to flag your tweet so that others can find it.)

Now, Twitter users are reporting that Iran's government might be blocking #IranElection. They're recommending others be used as well: #Iranians, #Tehran and #Iran9.

Update at 10:16 a.m. ET: At All Tech Considered, NPR's Eyder Peralta writes about how Twitter's being used by Iranians to find online servers that haven't been blocked by the government.

Update at 10:05 a.m. ET: "iranStreeNews" tweets that "people are gathering around in front of Radio and TV HQ in Vali Asr St The situation is calm and everyone is silent." It adds this — #GR88 — to the hashes.

Related story: The BBC reports about the videos that Iranians are managing to get out to the world.