Study of materials on case of A321 jet crash in Egypt is in final stage — Putin

MOSCOW, November 17. /TASS/. Russian A321 plane was blown up by homemade explosive device equivalent up to one kg of TNT, Russian Federal Security Service (FSB) chief Alexander Bortnikov said.

"It can be unambiguously said that this is a terrorist act," Bortnikov said.

According to him, the traces of a foreign-made explosive were found in the airliner debris and the passengers’ belongings.

"In the estimates of our specialists, a self-made explosive device with its power of up to 1 kilogram in TNT equivalent went off aboard the airliner, due to which the plane broke up in the air and this explains the spread of the plane's fuselage parts over a large distance," the Federal Security Service chief said.