U.S. stocks whipsawed on Thursday on the back of a report that the Russia investigation is intensifying.

Special Counsel Robert Mueller impaneled a grand jury in his investigation into Russia's involvement in the U.S. election, the Wall Street Journal reported minutes before the close.

The Dow Jones industrial average dipped lower on the report before closing 9.86 points higher at 22,026.10. The index also posted its seventh straight record close.

"At the least it puts the Trump administration in a legislative straight jacket. It's going to be very difficult to get laws passed while the constant drip of this news continues in the newspapers every day. I think it sets it back personally," said Jack Ablin, CIO of BMO Private Bank.

"I think the market has already adjusted. I kind of viewed tax reform as a call option that it really wasn't priced in if we get it great. I think the market as we can see survives and thrives without the benefit of pro-business policies," Ablin said.

The and the Nasdaq composite fell to session lows on the report, but managed to cut some of those losses before the close. The S&P closed 0.22 percent lower at 2,472.16, with energy leading decliners. The Nasdaq finished the session 0.35 percent lower at 6,340.34.

"That's just a piece of news that I saw here that I think shook the market here by [a few] points," said John Caruso, senior market strategist at RJO Futures. "It's just a quiet day. Really much a do about nothing. I think the markets are just waiting for the [jobs] numbers tomorrow."

The Dow was coming off a record-setting session, having broken above 22,000 for the first time on Wednesday, propelled by strong earnings from Apple. The tech giant posted better-than-expected quarterly results across the board.