The world’s richest man, Elon Musk, has completed his $44bn (£38.1bn) takeover of Twitter, according to US media and an investor in the firm. He tweeted “the bird is freed”, in an apparent reference to the deal closing. A number of top executives, including the boss, Parag Agrawal, have reportedly been fired. It brings to a close a saga that saw Twitter go to court to hold the multi-billionaire to the terms of a takeover deal that he had tried to escape.