WASHINGTON — House Speaker John Boehner declared Friday he would create a select committee to investigate the Benghazi attack, providing Republicans with a high-profile forum to target the Obama administration’s credibility ahead of crucial midterm elections.

Boehner said U.S. officials misled the American people after the Sept. 11, 2012, assault on the U.S. diplomatic outpost in Libya that killed Ambassador Chris Stevens and three other Americans. He said emails released this week showed the White House has withheld documents from congressional investigators and asked, “What else about Benghazi is the Obama administration still hiding from the American people?”

“Americans learned this week that the Obama administration is so intent on obstructing the truth about Benghazi that it is even willing to defy subpoenas issued by the standing committees of the people’s House,” Boehner, R-Ohio, said in a statement. “These revelations compel the House to take every possible action to ensure the American people have the truth about the terrorist attack on our consulate that killed four of our countrymen.”

Separately, the Republican chairman of the House oversight committee, one of several investigating the violence, said Friday he would subpoena Secretary of State John Kerry to testify about the administration’s response to the attack.

Republicans have accused President Obama and his top aides of seeking to deceive the public about the true circumstances of a major, al-Qaida-linked terrorist attack during the final months of the 2012 presidential campaign – charges that the president and other U.S. officials reject. But administration officials didn’t mention intelligence suggesting the Benghazi attack was distinct from simultaneous, anti-American protests elsewhere in the Arab world.

The State Department, which ordered an independent review days after the assault, called the notion that it has stonewalled multiple, ongoing congressional investigations “just false.”

“We’ve produced tens of thousands of documents. We’ve done nine hearings, 46 briefings,” State Department spokeswoman Marie Harf told reporters Friday. She called a select committee unnecessary: “How many more taxpayer dollars are we going to spend trying to prove a political point that in 18 months they haven’t been able to prove?”

The White House did not immediately respond to Boehner’s comments.

For Boehner, a select committee raises the profile of one of the Republicans’ main points of attack against Obama ahead of November’s elections, which could swing the Senate to GOP control. Benghazi is a rallying cry for the conservative GOP base and will be critical for fundraising and getting voters to the polls in typically low-turnout midterm contests.