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On the night of March 31, 2017, a rainfall-induced landslide event with more than 600 shallow landslides was triggered in Mocoa (Putumayo Department, southern Colombia). These landslides and the subsequent Mocoa Debris Flow (MDF) event caused, according to data published from the Unidad Nacional para la Gestion del Riesgo de Desastres (UNGRD, disaster risk management government agency), a catastrophic aftermath where 333 people were killed (including at least 118 children), 398 people were injured, and 76 people are still missing. In order to unravel the kinematic aspects of the MDF formation and the geomorphic setting which conditioned debris flow and landslide formation, high-resolution drone and satellite imagery, geomorphic indices, landslide inventory, and rainfall data from the event were analyzed. Flow discharge and velocity calculations associated to the MDF were calculated using three different methodologies which showed that the flow acquired a volume of ~ 2.6 × 106 m3 and an average velocity of 8–12 m/s, while the landslides developed in the Taruca, Taruquita, Mulato, and Sangoyaco basins contributed an estimated volume of about 298,000 m3. A landslide volume of about 3.44 × 106 m3 of material was calculated, from which less than 10% feed the MDF. Heavy rainfall and antecedent rainfalls were the triggering factors associated to shallow landslides developed on granitic rocks from the Mocoa monzogranite. Mass movements developed in residual soils from sedimentary rocks are more related to poor vegetation cover and intense anthropic activity such as extensive farming and deforestation. The recent activity of La Tebaida–Mocoa Fault and exhumation of the Mocoa monzogranite are considered as the main contributors to hillslope instability and landslide susceptibility. An active tectonic mountain front, steep slopes, and high drainage gradients are common at the study basins and are the key features controlling erosion and sedimentation rates. In this document, a brief introduction to the climatic, geological, and geomorphological characteristics of the involved basins and kinematic behavior of the MDF are presented.