Shares of Wal-Mart Stores fell nearly 5 percent after a news report alleged executives at the company's Mexican subsidiary carried out a vast bribery scheme and tried to hush it up.

Wal-Mart's stock price fell $2.70 to $59.75 in midday trading, wiping out its gains since the beginning of the year. The shares are still trading higher than their 52-week low of $48.31, reached on Aug. 10, 2011.

On Saturday, The New York Times reported that Wal-Mart executives failed to notify law enforcement officials even after its own investigators found evidence of millions of dollars in bribes. The newspaper said the company shut down its internal probe despite a report by its lead investigator that Mexican and U.S. laws likely were violated.

Wal-Mart says it is cooperating with authorities and looking into the matter.

Analysts gave differing opinions on whether investors should hold on to Wal-Mart's stock.

MKM Partners analyst Patrick McKeever advised holders to reduce their exposure. He added that while he wasn't sure if there would be a management shakeup, if that does occur it could also hurt the stock.

"Wal-Mart's current executive team has been starting to `gel' better over the past two to three quarters and is making progress with key initiatives after a period of leadership changes and inconsistency," he wrote "Accordingly, we would view any new changes in management as potentially disruptive to the improving fundamental trend we have seen recently."

Citi Investment research analyst Deborah Weinswig took the opposite view.

"We would use any weakness in the stock as an enhanced buying opportunity," she wrote. She said that after speaking with the company she believes Wal-Mart is dedicated to a "thorough and transparent review."