The body of Sunil Lawrence (25) was found hanging at his residence on Friday morning, police said.
He was employed by the same company of which a staffer, Rajasekharan Nair, was arrested and remanded on March 28
The explosive material was found in the cargo hold of the aircraft, which arrived in Thiruvananthapuram from Bangalore on March 21. A suicide note purportedly written by him 'congratulated' the police for the investigation into the crude bomb issue and said he was 'upset' over police questioning of innocent people, police added.