Device for closing or ligating a target tissue at the inner wall of a hollow organ, such as the digestive tract or other body lumens and hollow organs, characterized in that it comprises: • a proximal part provided with a first protrusion and a first slot, • a first arm and a second arm fixed to each other at said proximal part, said first arm being provided with a first distal end and a second slot, said second arm being provided with a second distal end, • a flexible tightening thread connecting said first and second arms (3, 4) at their respective first and second distal ends (19, 20), said flexible tightening thread forming a first loop passing from an outer side of the first arm into the second slot, • a flexible control thread comprising a second loop, wherein said device is designed to move: • from an open configuration, wherein: • said first and second distal ends (19, 20) are spaced apart from each other, • the control thread extends through said first slot toward the first loop, passes through it, and then returns to said proximal part to be fixed to said first protrusion with the second loop, • to a closed configuration, after a pulling force has been exerted on the control thread, wherein: • the control thread pulls along said first loop up to said first protrusion, so that the latter retains said first loop, • the control thread releases from said first protrusion, • said first and second distal ends (19, 20) are drawn toward each other by the tightening thread, for closing or ligating the target tissue. • a proximal part provided with a first protrusion and a first slot, • a first arm and a second arm fixed to each other at said proximal part, said first arm being provided with a first distal end and a second slot, said second arm being provided with a second distal end, • a flexible tightening thread connecting said first and second arms (3, 4) at their respective first and second distal ends (19, 20), said flexible tightening thread forming a first loop passing from an outer side of the first arm into the second slot, • a flexible control thread comprising a second loop, wherein said device is designed to move: • from an open configuration, wherein: • said first and second distal ends (19, 20) are spaced apart from each other, • the control thread extends through said first slot toward the first loop, passes through it, and then returns to said proximal part to be fixed to said first protrusion with the second loop, • said first and second distal ends (19, 20) are spaced apart from each other, • the control thread extends through said first slot toward the first loop, passes through it, and then returns to said proximal part to be fixed to said first protrusion with the second loop, • to a closed configuration, after a pulling force has been exerted on the control thread, wherein: • the control thread pulls along said first loop up to said first protrusion, so that the latter retains said first loop, • the control thread releases from said first protrusion, • said first and second distal ends (19, 20) are drawn toward each other by the tightening thread, for closing or ligating the target tissue. • the control thread pulls along said first loop up to said first protrusion, so that the latter retains said first loop, • the control thread releases from said first protrusion, • said first and second distal ends (19, 20) are drawn toward each other by the tightening thread, for closing or ligating the target tissue.