Twitter blocked in Pakistan - UPI.com KARACHI, Pakistan, May 20 (UPI) -- The Pakistani government blocked access to the micro-blogging Web site Twitter Sunday due to what it called derogatory discussions about the Prophet Mohammed. The Pakistan Telecommunication Authority asked Twitter to stop the allegedly offensive discussion, but the Web site "refused our request," Mohammad Yaseen, PTA chairman said. "I can't say for how long the Web site will remain blocked," he told Pakistan's Express-Tribune. Twitter officials said in an e-mail response they "cannot stop any individual doing anything of this nature on the Web site." The Pakistani government and Twitter representatives are still in negotiations over the blocked access, the Express-Tribune said. The Web site is still accessible in Pakistan by using mobile phones and secure browsers like Opera Mini, the newspaper said.