. To get rid of rats, a ‘Rat Hunt’ was started in 1902. . The French hired Vietnamese workers and paid them for each rat they caught. . Rats began to be caught in thousands but still there seemed to be no end. . Those who did the dirty work of entering sewers found that if they came together, they could get more money. . The bounty was paid when a tail was given as a proof that a rat had been killed. . So the rat catchers took to just clipping the tails and releasing the rats, so that the process could be repeated over and over again. . Ultimately, the French were forced to stop the bounty programme. . Besides this arrangement, the plague swept through the area.