More than 1,800 people nationwide signed an online letter to McDonald's Corp that calls for the fast-food chain to enhance security in its Chinese restaurants.

The petition, written in Mandarin and English, was created after the fatal beating of a 35-year-old woman in a McDonald's restaurant in Zhao-yuan, Shandong province, on May 28. Police say the assailants are members of a cult who attacked the woman after she refused to give them her cellphone number.

The incident triggered national outrage after a video of the beating went viral online.