Hours after Chris Kyle was killed, his book American Sniper went to both #1 (mass market) and #3 (hardcover) on Amazon. It also reached #3 on the Kindle bestseller chart. The audio and trade editions have also jumped over 3,000% in Amazon's sales rankings since the news broke. To date, the book has sold nearly 350,000 copies, according to Nielsen BookScan.

Kyle's next book, American Gun, was set to publish on May 14 from Morrow. The publisher is discussing plans for the book this week and plans to announce any changes soon.