Post-Blast Forensic Investigation Methodology: Lessons from Explosive Incidents in North East Nigeria

Post-blast forensic investigation provides critical intelligence for identifying explosive device components, perpetrators, and operational patterns in contexts of terrorist and insurgent activity. This study examines post-blast forensic investigation methodology and lessons learned from explosive incidents investigated by security agencies in North East Nigeria between 2019 and 2024. An empirical case analysis design was employed, reviewing thirty-five post-blast investigation reports from the Defence Intelligence Agency and the Nigeria Police Force Counter Terrorism Unit, conducting interviews with twelve post-blast investigators and explosive ordnance disposal specialists, and assessing available forensic laboratory capabilities. The study evaluates scene documentation protocols, explosive residue analysis methods, device component recovery procedures, and the integration of forensic findings with intelligence operations. Findings indicate that post-blast scene access and systematic evidence recovery are constrained by ongoing security threats in approximately sixty percent of incidents, resulting in incomplete evidence collection. Explosive residue analysis using ion chromatography and GC-MS was applied in forty percent of cases, with TATP and ammonium nitrate-based compositions most commonly identified. Device component analysis enabled partial manufacturing pattern identification in twenty-three cases, supporting tactical intelligence assessments. Recommendations include the development of rapid post-blast evidence recovery protocols adapted for active security environments and the procurement of portable explosive residue analysers for deployment in North East Nigeria. Keywords: post-blast investigation, explosive forensics, North East Nigeria, explosive residue, counter-terrorism.