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By Mary Wisniewski
CHICAGO, Sept 24 (Reuters) - Two more men have been charged with attempted murder, including one suspected of firing a military-style weapon into a crowd, in a shooting last week that wounded 13 people including a 3-year-old boy, Chicago Police Superintendent Garry McCarthy said on Tuesday.
The new charges brought to four the number of men charged with crimes related to a shooting that drew national attention because of the number injured.
McCarthy said the shooting was believed to be retaliation by members of a gang for an earlier shooting on Chicago's South Side, where poor neighborhoods have been plagued by gun violence.
McCarthy and Chicago Mayor Rahm Emanuel have struggled to contain street crime from gang wars in the poor, mostly African-American and Hispanic neighborhoods.
While Chicago's murder rate has subsided somewhat this year from a five-year high in 2012, it is higher than the more populous cities of New York and Los Angeles.
Illinois and the city of Chicago have loosened some gun laws this year, and McCarthy on Tuesday again called for the state legislature to toughen gun laws in order to curb the violence. (Reporting By Mary Wisniewski; Editing by Greg McCune and Jim Marshall)