Iran is smuggling weapons and ammunition to Hezbollah onboard commercial flights, according to Israel’s ambassador to the United Nations.

Danny Danon sent an urgent letter to the U.N Security Council this week alleging that officers from the Iranian Revolutionary Guards were using flights on Mahan Air, an Iranian airline, as a smuggling route into Lebanon and Damascus.

“The Iranian Al-Quds Force packs weapons, ammunition and missile technology to Hezbollah in suitcases and puts them on Mahan Air flights,” he said. “These planes fly directly to the airport in Lebanon or Damascus and from there the weapons are transferred on the ground to Hezbollah.”

He also alleged that the Shi’ite militia, which is based in Lebanon and is currently fighting alongside President Bashar al-Assad’s forces in Syria, had built up an underground stockpile of missiles larger than that of NATO.