Abstract: The invention relates to tamper evident tapes or soft packages, such as plastic bags or envelop, including new security features for sealing and rendering irreversible and unambiguously visible the opening of the package. The first new security feature concerns a plurality of U-shaped cuts extending through the tape, each U-shaped cut having an open end and a closed end defining a tearing edge. The U-shaped cuts are distributed and oriented along the tape so that the tearing edges thereof extend in multiple directions. The second new security feature is a thermochromatic layer present inside the tape and overlaying heat sensitive tamper-indicating areas also present in the tape. The thermochromatic ink layer intermingles with some markings also present therein and comprises an irreversible thermochromatic ink invisible at room temperature and activated at an activation temperature superior to the room temperature.