A series of Oxxo convenience stores have been attacked in central Mexico, authorities said on Monday, a sign that strikes targeting businesses may be spreading nearer to the capital. _0"> There were reports that as many as nine stores belonging to Mexico's largest convenience store chain, operated by Femsa , were attacked late on Sunday night, authorities in Hidalgo state and the state of Mexico said. Femsa said two of its Oxxo stores were set on fire and three were attacked by gunmen. Some employees suffered burns but none were seriously hurt, Femsa said in a statement. The State of Mexico surrounds most of Mexico City and borders Hidalgo to the north, and local state prosecutors said the attacks appeared coordinated, echoing recent assaults against businesses in the state of Michoacan in western Mexico. Michoacan, which shares a border with the State of Mexico, has been shaken by fighting between a violent drug gang and heavily-armed vigilante groups, presenting a