WOBURN (CBS) – The brother of the man who killed a Woburn police officer has now officially been charged in connection with the crime.

Fifty-year-old Arthur Cinelli pleaded not guilty on Wednesday to charges of conspiracy to commit masked armed robbery.

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He’s being held without bail.

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Prosecutors say Cinelli was text messaging his brother on how to carry out the robbery at a Kohls department store in Woburn.

Paroled convict Dominic Cinelli gunned down Officer Jack Maguire during the robbery.

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Cinelli was killed in an exchange of gunfire with Maguire.