The key facts about the Delhi building collapse are as follows:
HM Amit Shah has called off the Goa events in response to the Delhi building collapse. He has spoken to the Delhi CM, police, and NDRF chiefs to discuss the rescue efforts. The exact details of the building collapse, including the location and number of casualties, are not provided in the given evidence. However, it is mentioned that HM Amit Shah is actively involved in the rescue efforts and has taken steps to address the situation. The evidence does not provide information on the cause of the building collapse or the current status of the rescue operations.