Inquirer staff writer Mari A. Schaefer reports:

Police were busy over the weekend rounding up more suspects they believe are tied to an armed robbery group operating in Philadelphia and Delaware County.

Philadelphia police say they now have a total of seven people in custody, six of whom are charged in connection with a dozen robberies.

Many of the robberies targeted Asian American business owners.

On Friday, police arrested Shawn Davis, 18, of the 7900 block of Caesar Place, Philadelphia. Police said Davis confessed to a robbery in Middletown Township and named Charon Humphrey, 18, of the 7500 block of Wheeler Street in Philadelphia as an accomplice.

Davis and Humphrey were charged with robbery and aggravated assault, along with weapons and related charges.

"We are going to go back to 2006 with the assistance of the FBI to try and figure out how big this one is," said Lt. John Walker, of Southwest Detectives.

Arrested this weekend in connection to the robberies are Nuri Muray, 19, of 5600 Windsor Ave, Malik McCauley, of 2800 South 81st Street, Rickey Phillips, 18, of 2600, South 80th Street, and a 17 year old juvenile from the 8000 block of Pompey Place, all in Philadelphia.

Contact Inquirer staff writer Mari A. Schaefer at 610-892-9149 or mschaefer@phillynews.com

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