THE popular pro-independence Twitter account MSM Monitor has sparked questions after it suddenly disappeared.

The account – which had some 38,000 followers – tweeted from the handle @msm_monitor and was known for highlighting perceived bias in the mainstream media (MSM).

Fellow Twitter users noticed on Wednesday evening that the account’s tweets had disappeared, and its profile page showed the message: “This account doesn’t exist”.

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The account had tweeted earlier in the day about the letter from Ash Regan and Kate Forbes to SNP chief executive Peter Murrell asking for the publication of party membership numbers.

Then, just before 5pm, it posted: “Well, that's it for us folks. Social media was once a great tool for the indy cause, sadly no more. We're winding up the account in five mins. Good luck.”

The account was then deleted, taking that goodbye tweet with it.

Other Twitter users were quick to notice the disappearance of the account.

“Why has the brilliant @msm_monitor Twitter indy account stopped? Nigh on 40,000 followers. An amazing service. What the hell has happened?” one user wrote.

“MSM Monitor gone? Including every tweet about BBC bias with it? Says more than one likes to admit,” a second added.

“What in the hell just happened to MSM Monitor? Has the account been hacked or something?

“Zero signs they were going to leave Twitter, 10 minutes earlier they were talking about Regan and Forbes letter, and the next thing they’re gone. Some absolute fuckery is afoot here,” a third wrote.