Marshalltown’s police chief was one of fewer than half-a-dozen hand-picked to go to Washington last night for the announcement of a national crackdown on illegal aliens who are also gang members. Police Chief Lon Walker says his local cops teamed with the Immigration and Customs Enforcement agency in “Operation Community Shield.” Walker explains they didn’t publicize the crackdown till it was over. Out of the two-week nationwide push, there were just a few days devoted to the roundups in Des Moines and Marshalltown, he says. “We tried to keep it fairly low-key so some of the people we were looking for didn’t find out about it.” Chief Walker was flown to the nation’s capital to be there when Homeland Security Chief Michael Chertoff unveiled the operation Monday night. The chief says “it was pretty exciting” to be there for the announcement of the roundup, but also exciting to have the federal resources to help with Marshalltown’s crime problem. He says it helps send the message that Iowa towns won’t stand for gang activity. He says it shows gangs that law enforcement won’t tolerate their crimes, graffiti, or “the kinds of things that are not in our communities’ best interest.” After the crackdown was all over, Homeland Security announced it had resulted in nearly 600 arrests, many of them members of violent gangs in towns across the nation. Chief Walker says the estimate he’s seen is closer to 1000 illegal aliens arrested for also being members of gangs. Iowa’s largest crackdown in Operation Community Shield took place in Marshalltown, where the accused gang members are being held while immigration officials work on deporting them to Mexico.