* Investors concerned by report of Russian troop movements
* GDP revised higher in Q2, jobless claims fall
* Banks in focus after reports of cyber attacks
* Futures down: Dow 49 pts, S&P 6.25 pts, Nasdaq 11.75 pts (Updates prices, adds economic data)
NEW YORK, Aug 28 (Reuters) - U.S. stock index futures pointed to a lower open on Thursday after Ukraine's president said Russian forces had been brought into his country, bringing concerns over the volatile region back into focus and overshadowing some positive economic data.
* Worries over tension abroad had largely faded from Wall Street, with major indexes seeing few negative days over the past two weeks and both the Dow and S&P hitting records. However, the market has been looking for direction, with daily moves small and trading volume light.
* Ukraine's security and defense council said the border town of Novoazovsk and other parts of Ukraine's south-east had fallen under the control of Russian forces who, together with rebels, were staging a counter-offensive. Ukrainian President Petro Poroshenko called an urgent meeting of the security and defense council to decide the next steps to take in the crisis.
* While few U.S. companies have heavy exposure to either country, investors are worried about the potential fallout from any escalation in tensions, including increased sanctions. An index of major shares in Europe, which has much more exposure, fell 0.7 percent. If European growth is depressed by the conflict, that could have an indirect impact on the United States.
* Russia's dollar-denominated RTS index slumped 3.4 percent. The Market Vectors Russia Exchange-Traded Fund fell 3.1 percent to $24.35 in premarket trading.
* S&P 500 e-mini futures fell 6.25 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average e-mini futures fell 49 points and Nasdaq 100 e-mini futures lost 11.75 points.
* S&P 500 futures are indicating a drop of 0.3 percent, which would represent the biggest one-day decline for the benchmark index since Aug. 7. The index has risen for 11 of the past 14 sessions, and has closed above 2,000 for the past two days.
* The U.S. economy rebounded more strongly than initially thought in the second quarter, growing by 4.2 percent, the fastest pace of growth since the third quarter of 2013. Separately, jobless claims fell for a second straight week, the latest sign of improving labor market conditions.
* Bank stocks may be in focus after the Federal Bureau of Investigation said it was investigating media reports that several U.S. financial firms have been victims of recent cyber attacks. JPMorgan Chase & Co said it was investigating a possible attack; shares fell 0.6 percent to $59.23 before the bell.
* Williams-Sonoma Inc shares tumbled in premarket trading a day after it reported its second-quarter results and giving an outlook.
* Pending home sales data will be released at 10 a.m. (1400 GMT), with sales forecast to be up 0.5 percent. (Editing by Chizu Nomiyama)