A method, and an associated computer program product and computer system. One or more processors of a first computer located in a building monitor outgoing calls from a telephone in the building. The monitoring identifies an outgoing call dialed from the telephone. The one or more processors determine that the identified outgoing call is a telephone number of an emergency response center. In response to determining that the outgoing call is the telephone number of the emergency response center, the one or more processors transmit, via a communications network, emergency data having relevance to an emergency at the building to a second computer of the emergency response center and to emergency responders available to respond to the emergency at the building. The emergency responders are associated with the emergency response center. The emergency data transmitted to each emergency responder is specific to each emergency responder.