Jordan has foiled a suspected Iranian-led plot to smuggle weapons into the U.S.-allied kingdom to help opponents of the ruling monarchy carry out acts of sabotage, according to two Jordanian sources with knowledge of the matter.

The weapons were sent by Iranian-backed militias in Syria to a cell of the Muslim Brotherhood in Jordan that has links to the military wing of Palestinian group Hamas, the people said. The cache was seized when members of the cell, Jordanians of Palestinian descent, were arrested in late March, they said.

The alleged plot and arrests, reported here for the first time, come at a time of sky-high tensions in the Middle East, with an American-backed Israel at war in the Gaza Strip with Hamas, part of Iran's "Axis of Resistance" network of proxy groups built up over decades to oppose Israel.