Summary We report a case of accidental puncture of the small bowel during an ilioinguinal/iliohypogastric nerve block procedure for hernia repair. The diagnosis was made a few days later during a laparoscopic exploration owing to the progressive onset of clinical and radiological intestinal obstruction. A large, obstructing subserosal haematoma was found without any apparent perforation of the mucosa, and the damaged loop was resected. Such a complication has already been reported once in the literature after use of a long bevel needle for the puncture. This case is the first reported using an atraumatic short bevel needle. We discuss the technical aspects of the procedure and underline the fact that regional anaesthesia in children is never totally risk free.