The invention relates to an emergency vehicle (1) designed as a heavy truck, comprising a vehicle body (2) having an underbody assembly (9), a roof assembly (10) and at least one longitudinal wall (11, 12). Furthermore, a central longitudinal beam (8) is provided that is disposed in a manner extending in vehicle longitudinal direction. The central longitudinal beam (8) is joined directly and securely to the vehicle body (2), wherein it forms an integral constituent of the underbody assembly (9) of the vehicle body (2).