NEW YORK (CNN/Money) - U.S. stock futures fell early Thursday, signaling a selloff when markets open after new explosions rocked Istanbul.

At 9:10 a.m. ET, futures were decidedly lower, reversing earlier gains.

At least 25 people were killed and 390 injured by at least two explosions in the Turkish city, CNN Turk reported. One blast occurred in a shopping mall near the Istanbul offices of British bank company HSBC.

The explosions come less than a week after two car bombs exploded near synagogues in Istanbul, killing 25 people. They serve as a reminder of the terrorism fears that are a backdrop for trading throughout the world since the Sept. 11, 2001 attacks that destroyed New York's World Trade Center.

Hewlett-Packard's cautious outlook, anticipated results from Walt Disney and a handful of economic reports will also get the attention of investors when U.S. trading begins Thursday.

HP, the computer and computer products maker, posted fiscal fourth-quarter earnings late Wednesday that topped analyst expectations. But CEO Carly Fiorina said corporations were still being "tight with the purse strings" when it comes to technology spending.

Among U.S. stocks trading in Europe, Dow component HP was slightly higher.

After Thursday's close, Walt Disney (DIS: Research, Estimates) will become the last Dow stock to report earnings in calendar year 2003. The media and travel company is expected to post a fiscal fourth-quarter profit of 15 cents a share, up from 11 cents a year earlier, according to a consensus of analysts surveyed by First Call.

The company, which this week marked the 75th anniversary of the first Mickey Mouse cartoon, will also be scrutinized for guidance about several of its businesses, including theme parks, ABC TV and feature films.

For details of Wednesday's win, click above

Disney shares were lower in European trading.

On the economic front, fewer people filed for jobless claims last week as the U.S. job market continues its gradual recovery from an extended slump.

The Labor Department said 355,000 people filed new claims for unemployment benefits in the week ended Nov. 15, compared with a revised reading of 370,000 in the prior week.

Economists, on average, expected 365,000 new claims, according to Briefing.com.

Just after trading starts, the Conference Board will release its October index of leading economic indicators. That is seen rising 0.2 percent, compared with a 0.2 percent decline in September.

YOUR E-MAIL ALERTS Follow the news that matters to you. Create your own alert to be notified on topics you're interested in. Or, visit Popular Alerts for suggestions. Manage alerts | What is this?

At midday, the Federal Reserve Bank of Philadelphia puts out its regional economic activity index for November. The index is seen climbing to 30 from 28 in October.

The Dow Jones industrial average stemmed its recent slide to close up 0.7 percent Wednesday after a report showing stronger-than-expected home building activity. The Nasdaq composite index was a nearly 1 percent winner. (See chart for details)

Asian-Pacific markets, which were mostly closed prior to the Istanbul explosions, ended mixed; Tokyo's Nikkei index rallied 2.6 percent. European stocks fell in early trading. (Check the latest on world markets)

Treasury prices rallied after the blasts, sending the 10-year note yield down to 4.18 from 4.23 percent late Wednesday. The dollar weakened against the yen and euro.

Brent oil futures were unchanged at $29.78 a barrel in London. Gold gained ground in the wake of the explosions.