Intercepting the shipment, lining the interior of with some explosive (some putty that could hug all open space, or swapping out the batteries with custom ones that are half filled, etc), then wiring up a microchip that triggers when a specific code of 1’s & 0’s is received, or perhaps audio signal.
We’re talking about a state secret police here. There is no law or order. There is no “democracy”. They have billions of dollars in funding, and a mandate to do whatever they want with essentially zero consequences.
A solid 8 or 9 months beyond acceptable, but the only time it’s too late to stop arming genocidal regimes is after their goal is complete.