Where are Google messages pictures stores on phone

[SMYDSMITH]

If I take a picture in Google messages and send it I see in the chat and in my photo gallery
If someone send me a picture it shows in messages I have to save in gallery to have it show in gallery
If I delete from galley it stays in messages if I delete from messages it will be in gallery. Are the photos stored 2x or in messages cache or database in phone?

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