Turkeys block on access to Twitter violated freedom of expression and individual rights, the constitutional court said on Wednesday, the most significant legal challenge yet to a ban which caused public uproar and international condemnation. Turkeys telecoms authority TIB blocked access to Twitter on March 21 after Prime Minister Tayyip Erdogan said he would root out the network, following a stream of anonymously posted audio tapes purporting to expose corruption in his inner circle days ahead of nationwide elections. The constitutional court said it had sent its verdict to the TIB and the Transport Ministry, which also has responsibility for communications.