Samsung’s third-quarter profit jumped 91 percent to $5.97 billion on strong sales of the company’s Galaxy smartphones, but the company cautioned that things could slow in the holiday quarter.

The division that produces Samsung’s high-end smartphone devices accounted for almost 70 percent of operating profit for the quarter. Samsung did not release the exact number of units shipped, but IDC estimated the company shipped 56.7 million smartphones during the quarter.

Total revenues for the quarter hit $47.5 billion, up 26 percent from $37.6 billion a year ago.

Even as Samsung continues to put up record profits, the company warned of continued uncertainties in the broader economic environments in the United States and Europe.

Robert Yi, senior vice president and head of investor relations for Samsung, said in a statement that he expects market competition to intensify, but he added that the company will “do our best to sustain our earnings momentum throughout the fourth quarter by implementing strategies we have developed for our businesses.”

Looking ahead, Samsung expects year-end seasonality to push up demand for mobile devices, including tablet PCs, as new products make their way into markets with more competitive pricing. Still, the company hopes a flurry of new mobile devices hitting the market will prop up sales of application processors and image sensors that power smartphones and tablet PCs.

Samsung and Apple remain at one another’s throats, both in and out of the courtroom recently. Apple controlled 15 percent of the smartphone market during the third quarter, while Samsung grabbed a whopping 31 percent share, according to IDC.

Samsung continues to ride the wave of its Galaxy S III smartphone and Galaxy Note “phablet,” both of which have proved incredibly popular with consumers. Samsung’s Galaxy Note 2 just launched this week in the United States for $300 on contract at all of the top four major carriers here, as well as with U.S. Cellular.