The forward can be seen looking into the camera and then showing what appears to be his arm dripping with blood.
Other images show a black sports car which appears to have been destroyed in an accident. The post has since been deleted.
German tabloid Bild reported Sunday Boniface is "doing well considering the circumstances and is only slightly injured", citing a source close to the striker.
Boniface wrote on social media on Sunday "god is the greatest" and "god says my time hasn't come."
The forward's club Leverkusen are yet to comment publicly on the news.
The 23-year-old striker joined Leverkusen last season and played a key role as the club broke through for an unbeaten league and cup double - their first ever Bundesliga win - while receiving his debut Nigeria call-up.
This season he has seven goals in 10 games in all competitions. On Saturday, he missed a penalty but headed in the winner in a 2-1 home victory over Eintracht Frankfurt.
Leverkusen are away at French club Brest in the Champions League on Wednesday.
