Special Counsel Robert Mueller has subpoenaed the spokesman for former Trump campaign chairman Paul Manafort, demanding records related to his work for Mr. Manafort and seeking his testimony before a federal grand jury, according to a person familiar with the matter.

Jason Maloni was served Monday night with a subpoena seeking all records related to his work for Mr. Manafort since 2010. Mr. Maloni has represented the longtime political consultant only since March, so it wasn’t clear why the subpoena extends back that far.

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