ASHINGTON – Former Vice President Mike Pence has been subpoenaed by the Justice Department's special counsel overseeing inquiries into Donald Trump's efforts to subvert the 2020 election and the former president's retention of classified documents, a person familiar with the matter said Thursday.

 Former Vice-President Mike Pence speaks at Florida International University, Friday, Jan. 27, 2023, in Miami. Pence was talking about the economy and promoting his new book, "So Help Me God."© Marta Lavandier, AP 

It was not immediately clear what special counsel Jack Smith is seeking from Pence, but the demand likely marks a major escalation in the inquiry since Smith was appointed to manage the inquiries in November by Attorney General Merrick Garland. 

The subpoena to Pence was first reported by ABC News.

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The Justice Department declined comment. A Pence spokesperson also declined comment late Thursday.

Almost immediately after his appointment, Smith has been active on multiple fronts, issuing a flurry of subpoenas in December to local officials seeking communications with the former president, his campaign and advisers.

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Officials in Wisconsin, Michigan and Arizona confirmed that subpoenas had been received by county election authorities.

But the Pence summons indicates the inquiry has reached a possible inflection point related to Trump's efforts to cling to power.