Grand Theft Auto 6 has reportedly started development.

So from sources it looks like Rockstar at first wanted to make Grand Theft Auto 6 take place in Tokyo. “Rockstar visited the Japanese capital several years ago to assess its potential for a full GTA game, but ultimately pulled the plug on the idea, according to a source close to the company.” writes techradar, Usually before making a game Rockstar goes on trips pictures and such to get a feel of the area.
All the way back in 2003 Take-Two Interactive  filed trademarks for GTA: Tokyo and several other names. If Rockstar were to make the game outside the United States it would be a bigger challenge to what they want to do such as changing the brand of the cars.
This source that is close with Techradar has said that GTA 6 is in development but a location has yet to be confirmed. Keep in mind there will be a big announcement at E3 this year from Take Two Interactive weather its Red Dead Redemption 2 or another Grand Theft Auto. It’ll be interesting to see where Grand Theft Auto lands next.
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