Iran’s military kicked off its annual drill on Friday in the coastal area of the Gulf of Oman and near the strategic Strait of Hormuz, even as the authorities continue their crackdown on anti-government protests that have been under way for more than three months.

The strait is located at the mouth of the Persian Gulf and is crucial to global energy supplies, with about a fifth of all oil traded at sea passing through it.

State TV reports said commandos and airborne infantry would participate in the wargames, dubbed “Zolfaghar-1401”, along with drones, fighter jets, helicopters, military transport aircraft and submarines. Iran’s military is to fire missiles and air defence systems as well, it added.

The manoeuvres are aimed at “improving readiness in confronting foreign threats and any possible invasion,” the reports said.

Iran regularly holds such drills to improve its defensive power and test weapons.

Since mid-September, Iran has been shaken by anti-government protests. They were ignited by the death of 22-year-old Mahsa Amini who was detained by the country’s morality police.

The demonstrations rapidly escalated into calls for an end to more than four decades of the country’s clerical rule.