China. (Manchuria). 1947. Envelope written from New Zealand addressed to Harbin, China bearing New Zealand SG 604, 1/2d orange (pair) and SG 670, 2d purple tied by Auckland slogan '15th Aug 1947' routed via Hong Kong '1st Oct' with Shanghai and Chang-Chun (Manchuria) transits with framed instructional 'Mail Route to Destination/ Blocked, return to sender' in red on face and sent back via Hong Kong '24th Jan 48' with '4th Jun 48' hand-stamp in New Zealand. The Chinese People's Liberation Army controlled Harbin causing a break down in postal communications, the mail has reached Changchun in Manchuria but the Nationalists who controlled this area 'blocked' the letter from going on. The instructional was applied in Shanghai. Only four items known with this rare instructional.