Shares of companies such as Nokia Oyj (NOK1V), MEMC (WFR) Electronic Materials Inc. and an exchange-traded fund tracking financial shares made unusual moves today, spurring concern about computerized trading errors.

U.S. shares of Nokia jumped as much as 18 percent and fell more than 14 percent, while MEMC dropped as much as 20 percent. The Financial Select Sector SPDR Fund (XLF) jumped as much as 2.8 percent before erasing gains and trading lower. Other stocks making unusual moves between 10 a.m. and 11 a.m. New York time included Pandora Media Inc. (P), Hatteras Financial Corp. (HTS) and Las Vegas Sands Corp. (LVS)

"These wild, computer-driven market swings just add to the view that the market is somehow rigged,"Edward Bozaan, a managing partner at New York-based Cleargate Capital LLC, said in an interview. "I do not believe markets are rigged, but it's understandable how these mishaps can reduce confidence in the markets. The world does not need another flash crash."

The stock swings are the latest incident to fuel scrutiny of the electronic infrastructure of U.S. markets. Last week erroneous trades sent Kraft Foods Group Inc. up as much as 29 percent in the first minute of trading before they were canceled by exchanges. Regulators are studying ways to prevent electronic mishaps after a programming error almost sent Knight Capital Group Inc. into bankruptcy in August.

David Fuller's view The exchanges and regulators need to get a grip on this but I am not holding my breath.