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Indexes: Dow up 0.2%, S&P 500 up 0.1%, Nasdaq down 0.25%

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Cisco ( CSCO ) gains after raising FY forecasts

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UnitedHealth ( UNH ) down on report it faces criminal probe

(Updates with afternoon trading levels)

By Shashwat Chauhan and Pranav Kashyap

May 15 (Reuters) -

The S&P 500 teetered between gains and losses in a choppy

session on Thursday as elation from the U.S.-China tariff truce

tapered off, with UnitedHealth ( UNH ) among the biggest losers after a

report said the DoJ was investigating the insurer for fraud.

UnitedHealth Group ( UNH ) plunged 15% to a five-year low,

dragging on other health insurers such as Humana and

Molina Healthcare ( MOH ).

The Wall Street Journal reported that the U.S. Department of

Justice was conducting a criminal investigation into the company

for possible Medicare fraud. However, UnitedHealth ( UNH ) said it had

not been informed of a criminal probe by federal prosecutors.

"This is basically the third almost-catastrophic event for

the stock in the last three weeks. Now you've got this just

adding fuel to the fire," said John Belton, portfolio manager at

Gabelli Funds.

Executives at retail giant Walmart ( WMT ) said the company

would have to start raising prices later this month due to the

high cost of tariffs, even as its first-quarter U.S. comparable

sales beat expectations. Its shares fell 1.1% after it also did

not provide a second-quarter profit forecast.

Walmart ( WMT ) joins a spate of companies across sectors that

have either tweaked or pulled their forecasts, signaling that

corporate America is hunkering down for tariff-related

uncertainties.

On the brighter side, Cisco Systems ( CSCO ) jumped 6.3%

after the networking-equipment maker raised its annual forecasts

and named Mark Patterson its new CFO.

At 11:28 a.m. ET, the Dow Jones Industrial Average

rose 86.57 points, or 0.20%, to 42,136.78, the S&P 500

gained 5.75 points, or 0.10%, to 5,898.33, and the Nasdaq

Composite lost 48.77 points, or 0.25%, to 19,098.04.

Megacap and growth stocks were marginally lower after

falling earlier in the day, although Amazon.com ( AMZN ) lagged

with a 3% decline.

The energy sector was among the laggards as oil

prices slid around 3% on expectations of a U.S.-Iran nuclear

deal that could result in sanctions easing.

Stocks have see-sawed this week as equities jumped on Monday

and Tuesday after the U.S. and China announced a temporary

ceasefire on tariffs.

The gains were enough to drag the S&P out of the red

for the year, although it is still about 4% shy of record highs.

Earlier in the day, fresh data showed U.S. retail sales

growth slowed in April, while a separate report showed producer

prices unexpectedly fell last month.

The data dump follows a relatively tame consumer price

reading earlier in the week.

"Despite the de-escalation with China, the trade story isn't

over and it's still going to take time for tariffs to make

themselves felt in economic data," said Ellen Zentner, chief

economic strategist for Morgan Stanley Wealth Management.

U.S. Federal Reserve chair Jerome Powell said central bank

officials felt they needed to reconsider the key elements around

jobs as well as inflation in their current monetary policy

approach.

Advancing issues outnumbered decliners by a 1.36-to-1 ratio

on the NYSE, while declining issues outnumbered advancers by a

1.09-to-1 ratio on the Nasdaq.

The S&P 500 posted nine new 52-week highs and five new

lows, while the Nasdaq Composite recorded 34 new highs and 101

new lows.