Rihanna Tweets #FreePalestine ... Quickly Takes it Back

Rihanna just inserted herself in the middle of the Middle East conflict by tweeting, "#FreePalestine," but 8 minutes later deleted it.

It's unclear why Rihanna had the change of heart.

The tweet was posted shortly after the proposed Middle East cease fire fell apart.

Rihanna's tweet comes 3 days after NBA star Dwight Howard tweeted the same thing ... just like Rihanna, Howard deleted the post.

Howard later apologized for getting involved in international politics ... No such apology from Rihanna.

We reached out to Rihanna's rep ... so far no word back.

3:45 PM PT -- Rihanna has now tweeted out a message of peace for the Middle East.