The Turkish army sent soldiers about 1.5 miles into northern Iraq in an overnight operation on Tuesday, Kurdish officials said. A Turkish official said the troops seeking Kurdish rebels were still in Iraq by midmorning. Meanwhile, Secretary of State Condoleezza Rice made an unannounced visit to Kirkuk, the hub of Iraq's northern oil fields. The troops crossed into an area near the border with Iran, about 75 miles north of the city of Irbil, said Jabar Yawar, a spokesman for Kurdistan's Peshmerga security forces.About 300 Turkish troops crossed the border at 3 a.m., said Jamal Abdullah, a spokesman for the regional Kurdistan government. He said the region was a deserted mountainous frontier area. The U.S. Embassy in Baghdad declined to comment on reports of the Turkish operation.