A device and method for interconnecting the wires of a monitored alarm system into a telephone network interface without disturbing preexisting telephone line connections. The device is a connector assembly that is adapted to engage one of the connector modules present in a telephone network interface. The connector assembly electrically interconnects to a telecommunications pathway that passes through the telephone network interface. The connector assembly contains a wire connector that receives wires from the monitored alarm system. By connecting the alarm system wires to the connector assembly and connecting the connector assembly to the telephone network interface, the monitored alarm system is connected to external telephone lines without requiring existing telephone wire connections to be compromised.