The paper “Severity level assessment from semantically fused video content analysis for physical threat detection in ground segments of space systems” has been presented in 2nd International Workshop on Cyber-Physical Security for Critical Infrastructures Protection (CPS4CIP 2021) on 8th October 2021. G. Antzoulatos, G. Orfanidis, P. Giannakeris, G. Tzanetis, G. Kampilis-Stathopoulos, N. Kopalidis, I. Gialampoukidis, S. Vrochidis, and I. Kompatsiaris from the Multimodal Data Fusion and Analytics Group (M4D) of Multimedia Knowledge and Social Media Analytics Lab (MKLab) at ITI/CERTH, propose a novel framework to collect and analyse data detected from physical detectors, such as CCTVs, UAVs etc. The immediate response to the human-made attacks in ground segments of space systems are vital to the normal operation of these organisation. The framework, which developed in the content of 7SHIELD project, aims to detect timely, semantically fuse the obtained information and provide real-time assessments of the severity level of an attack.