A person familiar with the matter says the FBI is searching the Maryland home of John Bolton, who served in President Donald Trump’s first administration as national security adviser but later became critical of the president.

The searches were part of an investigation into the handling of classified documents, a person familiar with the matter said Friday.

The search of Bolton’s home comes as the Trump administration has taken steps to examine the activities of other perceived adversaries of the Republican president, including by authorizing a grand ju...