Iran has been preparing for months for a US operation to take control of Kharg Island, which President Donald Trump threatened to attack on Thursday, reports CNN

CNN reported in March, shortly after US military strikes on the island, that Iran has laid traps and moved additional military personnel and air defenses to Kharg. Iran’s build up of its defenses has included moving additional shoulder-fired, surface-to-air guided missile systems known as MANPADs to the island, sources previously told CNN Iran has also laid traps on the island with anti-personnel and anti-armor mines, the sources added, including on the shoreline where US troops could possibly land if Trump ordered a ground operation. US officials and military experts have said there would be significant risks in an operation to take Kharg, including a large number of US casualties.