Two cases of acute abdominal crisis due to intramural haemorrhage of the colon are presented with a review of the literature. One was a 10-year-old Nigerian boy; the haemorrhage occurred in the caecum and ascending colon. The other was a 69-year-old Caucasian woman with a haemorrhage in the colonic splenic flexure and descending colon. Both had a one-stage resection with anastomosis. The child survived; the woman died two days after the operation. The preoperative diagnosis of bleeding colonic lesions remains difficult especially when facilities for investigation are scarce. It is re-emphasized that in patients with acute abdomen it is not necessary to insist on accurate preoperative diagnosis before offering appropriate treatment.