Prosecutors have struggled to prove in court what the president and his aides have repeatedly said in public: that a network of leftist activists presents a serious threat to national security.
President Trump said Israel was responsible for the attack, but vowed to "massively" destroy the gas field if Tehran hit Qatar's energy facilities in retaliation.
The F.B.I. has opened an inquiry into Mr. Kent, who was the top U.S. counterterrorism official, according to people familiar with the situation. The investigation is said to predate his resignation this week over the Iran war.
The appointment raised concerns that the Trump administration would try to erode the news group's independence after picking a deputy who had been at conservative news channels for around 20 years.
Under the rules of the oversight committee, Attorney General Pam Bondi received a subpoena requiring her to appear. The panel's Republican chairman said he sent the summons reluctantly.
The nominee for homeland security secretary suggested that he had observed war firsthand but declined to provide details, which he said were "classified."
For the second time since the war began, Senate Democrats tried and failed to win passage of a resolution that would have halted the offensive until President Trump went to Congress for approval.