The British Forensic Explosives Laboratory (FEL) at the request of the Polish National Prosecutor's Office tested samples collected from the TU-154M jet that crashed in Smolensk for traces of explosive materials. According to "Sieci", which obtained results of these tests, on most of the 200 tested samples substances used to manufacture explosive materials were found.

After analysing and reviewing samples, we discovered presence of explosive materials on 107 wreckage fragments and on a sample taken from a victim's body. This was discovered using three independent methods – said former Defence Minister Antoni Macierewicz. He added that the substance discovered is most likely a material called RDX.

The Polish commission responsible for the re-investigation of the Smolensk plane crash said on Tuesday it had found traces of explosives on the wreckage of the aircraft and on the body of one of the victims.

On April 11th, 2018, the Committee for the Re-Investigation of the Smolensk Plane Crash at the Ministry of National Defence of the Republic of Poland (Re-Investigation Committee) presented its report and its new investigation findings concerning the causes behind the Smolensk plane crash. The Committee presented during a press conference a summary and a full report.