NEW: Documents reviewed by @business show that deep inside Russia’s war machine, the economic pain is real and the situation for many firms is deteriorating fast. The industry association in Nizhny Novgorod set out a litany of troubles facing companies in a letter, assessment and survey - all reviewed by @business - sent to a top regional official earlier this month, asking for help as it highlighted a sharp fall in investments, profits, orders and production amid a massive rise in borrowing costs and overdue payments. The situation is described as one of "serious concerns" with several firms now operating in "critical conditions", facing job cuts and depleting reserves. Not one civilian firm recorded a rise in order compared to a year ago - and the struggles are seeping into Russia's military industrial complex too.