Elon Musk has reportedly completed his takeover of Twitter. 

Mr Musk's US$44 billion (AU$68 billion) acquisition of Twitter has been formally completed, according to US media reports, which also say that his first move was to fire the social media company's top leadership team.

Mr Musk terminated the contracts of Twitter chief executive Parag Agrawal, chief financial officer Ned Segal and legal affairs and policy chief Vijaya Gadde upon the deal's close, according to unnamed sources.

Mr Agrawal and Mr Segal were reportedly in Twitter's headquarters when the acquisition closed and were escorted out, according to Reuters. 

Mr Musk has pledged to “defeat” spam bots on Twitter, make the content presentation algorithms publicly available, and prevent the platform from becoming an echo chamber for hate and division, while also limiting censorship.

The tech leader has not offered details on how he will achieve all this and who will run the company. 

He says he plans to cut jobs, leaving Twitter’s approximately 7,500 employees fretting about their future. 

He says he did not buy Twitter to make more money but “to try to help humanity, whom I love”.