Beijing – Two people were hacked to death and another nine injured by a man wielding a meat cleaver inside a Walmart store in China's southern manufacturing hub of Shenzhen, police in the city's Bao'an district said on Monday.A 30-year-old unemployed man was detained as a suspect in the Sunday night attack, police said in an online statement. The motive for the attack was not immediately known.Firearms are largely unobtainable for ordinary Chinese, and such attacks are more often carried out with knives or homemade explosives. Sales of knives have faced stricter regulations following high-profile attacks, some of which have targeted children at or just outside kindergartens and elementary schools.Perpetrators of most past attacks have been described as being mentally ill or bearing grudges against society, with social dislocation and a lack of resources for diagnosing and treating such conditions contributing to the problem, experts say.In one of the most horrific recent attacks, eight people were killed when a 22-year-old man detonated a homemade bomb at the front gate of a kindergarten school in eastern China. Only the suspect's surname, Xu, was released and no motive was provided.Walmart, headquartered in Bentonville, Arkansas, has been operating in China for more than 20 years. It had 439 stores in 189 Chinese cities by the end of 2016.