Twitter has been blocked in Pakistan on Sunday. The country's top telecommunications officials said that it was blocked because it refused to remove tweets considered offensive to Islam.

The tweets were promoting a competition on Facebook to post images of Islam's Prophet Muhammad, said Mohammad Yaseen, chairman of the Pakistan Telecommunication's Authority. Many Muslims regard depictions of the prophet, even favorable ones, as blasphemous.

The competitions is called Draw Muhammad Day, as tweeted the Welsh-Pakistani photographer, Sufian Ahmed

Must have something to do with #DrawMuhammadDay RT @fursid: Why #twiter is blocked on many ISPs in #Pakistan?

— sufian ahmed (@paktographer) May 20, 2012

The news comes few hours after the Pakistani Minister of Interior, Rehman Malik, tweeted:

Dear all, I assure u that Twitter and FB will continue in our countryand it will not be blocked. Pl do not believe in rumors.

— Rehman Malik (@SenRehmanMalik) May 19, 2012

According to the Pakistani officials, “Both Facebook and Twitter were involved. We negotiated with both. Facebook has agreed to remove the stuff but Twitter is not responding to us”. Matih Abbas commented on this:

So Facebook now ranks less in blasphemy than twitter ? LOL #Twitterban

— Matih Abbas (@mat1h) May 20, 2012

In fact, Facebooks also has been blocked for a while in Pakistan a couple of years ago.

Faizan Lakhani wondered:

They cant stop corruption, they cant stop terrorism, they cant ban killers, but they can ban Twitter. #Pakistan

— Faizan Lakhani (@faizanlakhani) May 20, 2012

Finally, it worth mentioning that few months ago, in March 2012, the Pakistan Telecommunications Authority published a request for proposals for the “deployment and operation of a national level URL Filtering and Blocking System”. Yet, seems that the government's effort are not succeeding so far, as Pakistanis still find ways to reach twitter even after the block. Aaqil Mahmood published some tips for breaking the block in his blog. And Yannis Koutsomitis ‏tweeted that TweetDeck and other twitter applications are still working.