• Former Vice President Mike Pence expressed "deep concern" about the FBI's search of ex-President Donald Trump's resort home Mar-a-Lago.
• Pence's tweets echoed complaints by the former president's supporters that the DOJ and Biden-appointed Attorney General Merrick Garland are unjustly targeting Trump and his allies.
• Trump and his supporters have attacked Pence since the former vice president resisted Trump's calls for him to challenge President Joe Biden's victory in the 2020 election.

Former Vice President Mike Pence expressed "deep concern" Tuesday about the FBI's search of ex-President Donald Trump's resort home Mar-a-Lago, calling it "unprecedented" and pressing the Department of Justice to explain the shocking move.

"No former President of the United States has ever been subject to a raid of their personal residence in American history," Pence said in a trio of tweets.

Pence's statement came a day after Trump announced that a "large group of FBI agents" conducted an unannounced "raid" at the Palm Beach, Florida, resort, which has been Trump's official residence since he left the White House.

"They even broke into my safe!" said Trump, who was in New York City on Monday when the FBI searched his home.

I share the deep concern of millions of Americans over the unprecedented search of the personal residence of President Trump. No former President of the United States has ever been subject to a raid of their personal residence in American history.

— Mike Pence (@Mike_Pence) August 9, 2022

The search was related to a Justice Department probe into whether laws were broken when 15 boxes of White House records — which included some documents marked as classified — ended up at Mar-a-Lago instead of the National Archives, NBC News and other outlets reported.

To obtain a search warrant, federal investigators must show a judge that there is probable cause to believe a crime has been committed and that there may be evidence related to that crime in the location they are targeting.

There are multiple active investigations at the state and federal level related to Trump, his business and his family. In addition to the probe of records at Mar-a-Lago, the Justice Department is reportedly investigating events leading to the Capitol riot.

A grand jury has also been impaneled in Georgia as part of a probe into efforts by Trump and others to meddle in that state's election in 2020. The New York attorney general's office is also conducting a civil probe into the Trump Organization's business practices.

Pence's tweets echoed complaints from other Republicans who claim the Justice Department and Biden-appointed Attorney General Merrick Garland are unjustly targeting Trump and his political allies.

"After years where FBI agents were found to be acting on political motivation during our administration, the appearance of continued partisanship by the Justice Department must be addressed," Pence wrote.

"Yesterday's action undermines public confidence in our system of justice and Attorney General Garland must give a full accounting to the American people as to why this action was taken and he must do so immediately," Pence tweeted.

The statement marked a rare public reference to Trump by his former vice president. Trump and his supporters have castigated Pence since he resisted the ex-president's calls for him to challenge President Joe Biden's victory in the 2020 election.

Pence on Jan. 6, 2021, rejected a dubious legal theory pushed by Trump and his allies. They claimed the vice president had the power to decline key states' Electoral College results.

Pence's refusal to throw out lawfully certified electoral votes contributed to fury among thousands of Trump supporters, who descended on the Capitol and stormed the building. The riot forced lawmakers, and Pence, into hiding, and delayed Congress from confirming Biden's win over Trump.

The House select committee investigating the riot said Pence's life was in danger on Jan. 6.

Pence, who appears to be considering a future presidential run, said in February that he thinks "Trump is wrong" to believe the vice president could unilaterally reject the presidential election results.

"And frankly, there is no idea more un-American than the notion that any one person could choose the American president," the former vice president said.

Senate Minority Leader Mitch McConnell, another Republican whose relationship with Trump has soured, was noticeably silent on the raid as of Tuesday afternoon.

But many of Trump's GOP allies showed outrage toward the Justice Department after Monday's search and suggested politics motivated the raid.

"I've seen enough," said House Minority Leader Kevin McCarthy, R-Calif., in a statement Monday night. The DOJ "has reached an intolerable state of weaponized politicization," he said.

McCarthy vowed to investigate the department and "leave no stone unturned" after the November midterm elections, when Republicans could win control of the House.

"Attorney General Garland, preserve your documents and clear your calendar," his statement added.

Other vocal Trump supporters in Congress echoed McCarthy.

"If the FBI can raid a U.S. President, imagine what they can do to you," tweeted House Republican Conference Chair Elise Stefanik of New York.

"Launching such an investigation of a former president this close to an election is beyond problematic," said Sen. Lindsey Graham, R-S.C.

Both Republican U.S. senators from Florida, Rick Scott and Marco Rubio, accused the Biden administration of persecuting political enemies.