The head of Russia’s security service is confirming this morning that the plane crash over Egypt last month was the result of a terrorist attack.

The security chief says traces of foreign explosive have been found — and that the plane broke up in the air after a homemade device equivalent to a kilogram of TNT was detonated.

Islamic State militants have claimed responsibility for bringing down the Metrojet Airbus 321-200, which crashed over the Sinai Peninsula on Oct. 31, about 23 minutes after take-off from a Red Sea resort.

Russian president Vladimir Putin has vowed to hunt down those responsible, saying, “We’re going to look for them everywhere, wherever they are hiding.  We will find them in any place on earth and punish them.”

He’s instructed the Russian military to review how Russia’s air campaign in Syria can be modified to intensify attacks on militants.

Russia is offering a $50-million dollar reward for information on who brought down the plane.

All 224 people on board, most of them Russian tourists, were killed in the crash.