Richard Drew/AP

The Dow Jones Industrial Average, S&P 500, and Nasdaq Composite all plunged Friday, capping off a volatile week for US stocks.

The Dow posted its worst week since 2008, and the S&P 500 posted its worst week since August of 2011.

Follow the US market action here.

Stocks tumbled Friday, with the major averages all closing firmly in negative territory. The Dow fell 414 points, or 2%, bringing its weekly decline to 6.87%.

The S&P 500 also shed 2% on Friday, while the Nasdaq Composite fell 3% — entering a bear market, or down 20% from its highs — as some big tech names posted steep declines. Apple fell nearly 4% while Amazon plunged almost 6%. Google parent Alphabet tumbled 3%.

The losses accelerated in the final hour of trading, and stocks closed just barely off session lows.

"So much for the the stock market acting well in the days surrounding Fed meetings!" Matt Maley, an equity strategist at Miller Tabak, wrote in a note to clients earlier in the day.

Indeed, the Federal Reserve's fourth rate hike this year, announced on Wednesday, pummeled stocks as equity investors feared rising interest rates would eat into corporate profits.

Other market watchers said recent weakness within the equity market was borne from fears surrounding the special counsel Robert Mueller's investigation.

"We continue to believe this decline is due to the Mueller investigation and the aforementioned 'selling into a vacuum.' When it ends is unknowable, but selling stampedes tend to last 17-25 sessions, and today is session 13 in the skein," Jeffrey Saut, the chief investment strategist at Raymond James, wrote in a note to clients early Friday.

Now read:

NOW WATCH: The equity chief at $6.3 trillion BlackRock weighs in on the trade war, a possible recession, and offers her best investing advice for a tricky 2019 landscape