Twitter went down partially for over 90 minutes on Monday evening. Users noted experiencing a delay in the 140-character message sending service for a period of 25 to 45 minutes.

The issue involved a delayed appearance of tweets on the users' timelines from 16:51 PST to 18:30 PST on Jan. 5. It spanned platforms, affecting users of Twitter.com, Twitter for mobile and third-party Twitter clients, such as Tweetdeck.

"Between 16:51 and 18:30 PST today, users experienced a delay in tweets appearing in their timelines. This issue has been fully resolved," wrote Twitter. "We apologize for any inconvenience caused by this."

Users complained that their timelines were either lagging or not updating.

"What is going on with Twitter lately? It was down for 3 hours last week, couldn't log in and now it's down again? #BadTwitter #TwitterDown," tweeted Trisha Achenbach.

"I am all alone on Twitter. Only seeing my own tweets. It's like social solipsism. #TwitterDown," said @DavidClinchNews.

"I haven't seen a tweet in over 20 minutes -- I am not sure on the status of other survivors. Still good on supplies. #TwitterDown," said Michael Rusch (@weeddude).

The users have flagged the problem with the #TwitterDown hashtag. When the service was restored, the same hashtag was used to report the status.

There's no word yet on Twitter explaining the cause of the outage.

Apart from the delayed tweets, other issues involved missing retweets or favorites, delayed mentions, delayed or nonexistent timeline updates and direct messages that are disjointed.

"Twitter is down, but no one can confirm it because ... twitter is down. RIP," said Nick Lehman (@nicklehman1992).

"Twitter is weird tonight ... It is like I'm talking to myself. May as well put down my iPad and shout at the TV like pre-Twitter days #RAW," tweeted Simon Wilson (@the_sim).

"I can tweet, but I can't read anyone else's. So, this is what following no one feels like. #TwitterDown," said Kaitlyn Herzog (@KaitlynMKE).

"Is this national nightmare over yet? #TwitterDown," said Micah Grimes (@MicahGrimes).

Monday night's issue on Twitter is just one of several issues that users dealt with on the site. On Dec. 28, it was noted that some users were unable to log in to Twitter. The company explained that it was caused by a bug in the front end code, which they resolved through a patch.