China market regulator has summoned four hog producers over potential antitrust behaviour, Reuters reported, citing state media CCTV on Monday.

An agreement signed in late June by the four hog producers - Muyuan Foods, Wens Foodstuff Group, Twins Group and CP Food - not to poach each other violated "the spirit of China's anti-monopoly law," China's State Administration for Market Regulation cited it as grounds for the summon, according to the CCTV report.