Abstract: A device for marking a selected tissue location within a patient's body comprises at least two markers (16, 116, 216) pre-loaded into a hollow needle (18, 118, 218) and packaged in a sterile fashion with a stopper (28, 128, 218) to prevent a stylet (27, 127, 227) inserted into the needle (18, 118, 218) from releasing the markers (16, 116, 216) during shipping. An indexing mechanism (28/29, 128/129, 228/229) is also provided for releasably blocking the stylet (27, 127, 227) at successive predetermined levels of insertion into the needle with each level of insertion being associated with the discharge of a single marker (16, 116, 216).