A Hezbollah lawmaker in Lebanon acknowledged in a rare admission Thursday that a 1,100 pound shipment of explosives seized last week by national authorities belonged to the Iran-backed group.

"The vehicle and its cargo belong to the resistance" against Israel, lawmaker Hassan Fadlallah said, calling for the immediate release of those arrested during the seizure.

The explosives were seized on a road linking eastern Lebanon to Beirut, saying it constituted "capabilities" used by Hezbollah against Israel.

Lebanese Prime Minister Nawaf Salam has said the government will no longer tolerate any possession of "illegal weapons" by non-state groups.

He...