In a tweet, Turkey's president has hit out at the government ban of Twitter, as opposition leaders vowed to mount a legal challenge to the measure that came just days ahead of crucial polls.

The popular micro-blogging site, one of several that has been used to publish allegations of corruption in Prime Minister Recep Tayyip Erdogan's inner circle, went dark in Turkey late on Thursday, just hours after the embattled leader threatened to "wipe out" the social network.

Al Jazeera's Omar Al-Saleh reports from Istanbul.