WASHINGTON (AP) — The Latest on investigations into Russia and Donald Trump's presidential campaign (all times local):

8:20 p.m.

The top Democrat on the House Intelligence Committee is accusing President Donald Trump's White House of placing a "gag order" on former chief strategist Steve Bannon, barring him from answering many questions as part of the panel's investigation into Russian election interference.

Rep. Adam Schiff of California says Bannon refused to answer questions about his time in the White House or his work on the presidential transition. Bannon's refusal prompted a subpoena from the committee's Republican chairman, Rep. Devin Nunes of California.

Schiff says that was the first time Republicans on the committee had issued a subpoena in response to a witness refusing to answer questions at the instruction of the White House. Schiff says that the committee plans to bring Bannon back for another round of questioning.

Steven Bannon, a former aide to US President Donald Trump, arrived to testify before the House Intelligence Committee in a closed session on Tuesday. (Jan. 16)

__

7:30 p.m.

Former White House chief strategist Steve Bannon is refusing to answer questions from a House committee about his work during the presidential transition or his time working in President Donald Trump's White House.

That's according to Jack Langer, a spokesman for Rep. Devin Nunes of California, the Republican chairman of the House Intelligence Committee. Langer tells The Associated Press that Bannon would not discuss those topics during a day-long, closed-door interview on Capitol Hill.

In response, Nunes issued a subpoena to compel Bannon to answer the committee's questions. It's unclear whether Bannon was more forthcoming afterward.

Earlier Tuesday, a White House official said the president did not invoke executive privilege to prevent Bannon from answering the committee's questions. That official spoke on condition of anonymity to discuss internal deliberations.

__

7 p.m.

The House Intelligence Committee subpoenaed former White House chief strategist Steve Bannon on Tuesday in a showdown over whether he could be forced to testify in the panel's Russia investigation.

Bannon walked into a closed-door meeting with House members Tuesday morning and was still being grilled Tuesday evening. Lawmakers wanted answers from him about President Donald Trump's thinking when he fired FBI Director James Comey.

The committee's Republican chairman, Rep. Devin Nunes of California, said he issued the subpoena, but he declined to discuss why or what questions he hoped to compel Bannon to answer.