House Speaker McCarthy tweeted on Sunday that US Attorney David Weiss must answer questions about whistleblower allegations that the Justice Department intervened in the case to protect Biden's son.
Former US president Donald Trump blamed US President Joe Biden for the conflict in Russia, and accused him of colluding with China.
Merrick Garland spoke publicly for the first time since Hunter Biden was criminally charged on Tuesday with two misdemeanor counts of willfully failing to pay income taxes.
The Justice Department said on Tuesday that Hunter Biden, 53, has agreed to plead guilty to two misdemeanor charges of willfully failing to pay income taxes.
Hunter Biden appears to be the first child of a sitting president to be indicted.
Gal Luft rejected the accusations leveled against him and claimed he was arrested in relation to Hunter Biden's criminal investigation.
Congressional Republicans set out on an investigation into who had access to President Biden's classified documents on hand.