By Andy Sullivan and Diane Bartz

WASHINGTON (Reuters) -- The top Democrat in the U.S. Senate called on Congress to examine fantasy-sports betting services on Tuesday after reports that an employee with access to insider information placed bets in the unregulated multi-billion-dollar industry.

"There's absolutely scandalous conduct taking place through those programs, fantasy sports," Senate Democratic Leader Harry Reid told reporters.

"I think it also should be a warning-shot to everybody that online gaming is a real scary thing and we ought to look at all of it," said Reid, who is a former Gaming Commission head in Nevada, a hub of the industry.

Reid's statement raises the prospect of congressional scrutiny and possibly new regulations for websites such as DraftKings and FanDuel that have drawn millions of users who pay a fee to compete for daily prizes by assembling teams that accumulate points based on how the players did in actual games.

Meanwhile, Representative Frank Pallone and Senator Bob Menendez, both New Jersey Democrats, asked the Federal Trade Commission to look into the fantasy scandal.

Both companies confirmed on Monday that a DraftKings employee won $350,000 from a $25 entry fee in an American football contest. According to a trade group, the employee inadvertently released player data - a practice that experts liken to insider-trading.

The two privately held companies say they temporarily banned employees from playing daily fantasy sports.

The House of Representatives could hold hearings this fall, said Pallone, the top Democrat on the Energy and Commerce Committee. The Republican-controlled committee is looking into the issue, a spokesman said.


Fantasy sports deny ‘insider’ wrongdoing

The issue could draw the attention of conservatives like House Judiciary Committee Chairman Bob Goodlatte, who has pushed to outlaw other forms of online gambling.

Critics say daily fantasy sports services allow fans to bet with a frequency akin to gambling and led to the rise of the two industry leaders.

So far, fantasy sports services have escaped the restrictions that have outlawed sports betting in most states.

The Fantasy Sports Trade Association has spent $80,000 over the past year to defend its interests in Washington, lobbying records show. The group declined to comment.

Online gambling foes who are pushing for a nationwide ban on casino-style Internet gambling are not yet targeting fantasy sports services. But they may raise the DraftKings incident as another example of perils of online betting as they make their case, according to a former congressional aide now working to ban online gambling.

(Reporting by Andy Sullivan and Diane Bartz, writing by Andy Sullivan; editing by Alan Crosby)