Abstract: The opener consists of two hydraulic actuators which are adapted to act along in two different directions in an horizontal plane, one of said directions being parallel or substantially parallel to the surface of the closed and locked door which is to be opened and the other direction being normal to said door surface. Jamb-engaging elements are associated with a first of the actuators, operation of said actuator causing the elements to engage the door jambs very firmly; operation of the second of the actuators pushes the closed/locked door inwardly out of the door frame.