Turkish forces pressed ahead with ground operations against Kurdish rebels in Iraq on Saturday after the military reported that five troops and several dozen rebels had been killed in the cross-border fighting.

The U.S.-backed Iraqi government said Turkey had assured it that the operation, Ankara's first major ground incursion against Kurdish rebel bases in nearly a decade, would target only rebels who have staged hit-and-run attacks on Turkish targets from hideouts in northern Iraq.

A Turkish soldier was killed and another was wounded in a land mine blast on Saturday in the Turkish province of Bingol, nearly 300 kilometers (190 miles) from the border, local media said.

Two buses and five vans on Saturday ferried soldiers toward the Turkish border town of Cukurca, which lies north of the combat area, Dogan news agency reported. Vehicles used to carry ammunition were seen returning from the border area.

Two Turkish warplanes were seen flying toward Cukurca, Dogan said, but it was unclear whether they were on a bombing mission.

Further west, soldiers in Besta swept roads for possible land mines. Dozens of troops carrying assault rifles, light mortars, rocket-propelled grenades and sleeping mats patrolled near mountains with snow-covered peaks.

Supported by air power, Turkish troops crossed into northern Iraq late Thursday in an offensive that marked a dramatic escalation in Turkey's fight with the rebel Kurdistan Workers' Party, or PKK, even though Turkish officials described the operation as limited.

The Turkish military said five troops and 24 Kurdish rebels were killed in clashes. At least 20 more rebels were killed by artillery and helicopter gunships, it said. Artillery units positioned near Cukurca could be heard firing shells across the border on Friday evening, Dogan agency reported.

The Iraqi government said Saturday that fewer than 1,000 Turkish troops had crossed the frontier. Government spokesman Ali al-Dabbagh said Turkish commanders had assured Iraq that the "operation will be a limited one and it will not violate certain standards that they have set."

Al-Dabbagh said Iraq's president and prime minister had spoken to Turkish officials.

"We know the threats that Turkey is facing but military operations will not solve the PKK problem. Turkey has resorted to military options, but this never resulted in a good thing," al-Dabbagh said. He acknowledged that Turkey was "suffering from the terrorist PKK organization."

On Friday, a military officer of the U.S.-led coalition in Iraq said on condition of anonymity that several hundred Turkish soldiers had crossed the border. The coalition has satellites as well as drones and other surveillance aircraft at its disposal.

Sky-Turk television said about 2,000 Turkish soldiers were in Iraq, operating against rebel camps about 2-2.5 miles in from the border. NTV television said a total of 10,000 soldiers were inside Iraq in an operation that had extended 6 miles past the frontier. The activity was reportedly occurring about 60 miles east of Cizre, a major town near the border with Iraq.

It was not possible to confirm independently the size or scope of the attack on the PKK, which is considered a terrorist group by the United States and European Union. CNN-Turk television, citing Turkish security officials, said the operation could last two weeks.

The advance was the first confirmed Turkish military ground operation in Iraq since the U.S.-led invasion that toppled Saddam Hussein in 2003. Turkey's army is believed to have carried out unacknowledged "hot pursuits" in recent years, with small groups of troops staying in Iraq for as little as a few hours or a day.

Turkey staged about two-dozen attacks in Iraq during the rule of Saddam, who conducted brutal campaigns against Iraqi Kurds. Some Turkish offensives, including several in the late 1990s, involved tens of thousands of soldiers. Results were mixed; rebels suffered combat losses but regrouped after Turkish forces withdrew.

The PKK militants are fighting for autonomy in predominantly Kurdish southeastern Turkey and have carried out attacks on Turkish targets from bases in the semiautonomous Kurdish region of northern Iraq. The conflict started in 1984 and has claimed as many as 40,000 lives.

Turkey's government has complained that Iraqi and U.S. authorities were not doing enough to stop guerrilla operations. The Turkish air force has been staging air raids on PKK forces in the north since December with the help of intelligence provided by the U.S., a NATO ally.

"We continue to express our absolute solidarity with Turkey about the PKK. This is a common enemy of the United States and Turkey," U.S. Secretary of State Condoleezza Rice said on Friday in Washington. "It is also an enemy of the Iraqi people and the Iraqi government because the Iraqi territory cannot be used for terror, should not be used for terrorist attacks against Turkey."

Rice, however, said: "We've also been very clear, though, that stability and progress for Iraq is in the interest of Turkey. And so, everything should keep in mind that nothing should be done to destabilize what is a fragile but improving situation in Iraq."