A 61-year-old male on anticoagulant therapy underwent an endoscopic multiple colon polypectomy in our Department according to established procedures. Several days later he developed an intramural colonic hematoma, which burst into the peritoneal cavity leading to fatal intra-peritoneal hemorrhage. Herein we present the case and discuss the causative role of the anticoagulant therapy but also of the endoscopic procedure per se.