Record oil and gas prices sent the markets tumbling during the midday with the Dow plunging 117 points to 12,708. Nasdaq plummeted 35 points to 2373.

On the upside

Analysts upgraded Volterra Semiconductor (Nasdaq: VLTR) after strong demand boosted the company's first quarter earnings above expectations.

Zoran (Nasdaq: ZRAN) narrowed first quarter losses and forecast second quarter revenue ahead of analyst estimates.

Shares of Las Vegas Sands (NYSE: LVS), which operates the Sands Macao and Venetian Macao in Macau, climbed after the Chinese government said that no new casino licenses will be issued.

On the downside

UAL (NYSE: UAUA) blamed record fuel expenses for a $537 million loss in the first quarter. The parent of United Airlines also announced flight cuts as well as the elimination of 1,100 jobs.

Omnicell (Nasdaq: OMCL) reported lower first quarter earnings and cut its full year outlook prompting downgrades.

Second quarter earnings for BJ Services (NYSE: BJS) tumbled to fall short of estimates as prices dropped in North America. The oilfield services firm also forecast third quarter results well below expectations.

In the broad market, declining issues outpaced advancers by a margin of more than 3 to 1 on the NYSE and by nearly 7 to 2 on Nasdaq. The Russell 2000 which tracks small cap stocks plummeted 17 points to 701.