The teenager is among a half dozen men in New York and New Jersey whom authorities have arrested since June.
A homemade explosive device blew up on the plane, Alexander Bortnikov said.
The recording will be analyzed with a technology "unavailable in most countries."
CAIRO — Within months of the military takeover here two years ago, a little-known group calling itself Ansar Beit al-Maqdis
The "chatter" included a boast of taking down the plane on Saturday and how it was done.
"We cannot be certain that the Russian airliner was brought down by a terrorist bomb, but it looks increasingly likely that that was the case," Cameron said.
The new evidence suggests an onboard explosion may have downed the airliner, killing 224.
The large area over which fragments were found indicates that the jet disintegrated while flying high, said the head of Russia's federal aviation agency.