In the concept that coronal mass ejections (CME) are usually originated in large closed magnetic field regions which are found in the coronal streamer belt near the solar surface, we have used a thermal driving force so strong that portions of the closed magnetic fields were carried away by the strong disturbance. A CME-shock system is obtained in the inner corona. The legs of loop-like CMEs are again obtained at the interface between the coronal open and closed magnetic fields. However, there is no counterpart in outer space. The shock is a combined one with an intermediate shock near the equator at its early stage. Ultimately, it becomes a pure fast shock. A plasmoid with higher density and bubble-like magnetic fields is formed behind the MHD shock wave. It propagates at high speed. The results show that the high-speed plasmoid does not propel the MHD shock in front of it; rather, the plasmoid forms behind the MHD shock. ¿ 2000 American Geophysical Union