Tensions escalate as Israel strikes key Iranian oil and gas sites, including the South Pars field, a first in decades of conflict. This action follows earlier exchanges of attacks, resulting in casualties on both sides.

Meanwhile, the hit on the Fajr-e Jam Gas Refinery, in Bushehr province, threatens to disrupt Iran’s domestic electricity and fuel supplies, particularly for the southern and central provinces, which are already under huge stress. In Iran, blackouts cost the economy about $250m a day, according to the government’s estimates.

Iran has been forced to partially shut operations at the South Pars gas field after a fire caused by an Israeli air strike. The South Pars gas field is the biggest in the world. But what do we know about it?