ANKARA, Turkey -- Turkish warplanes struck Wednesday at mountain caves that the military said Kurdish rebels were preparing to use as winter hide-outs in northern Iraq, the third cross-border air assault in 10 days.
The planes conducted "an effective pinpoint operation" against the separatist rebels of the Kurdistan Workers' Party, or PKK, the military said in a statement posted on its Web site. However, no rebel deaths from the strikes were immediately reported.
The PKK has waged a war for autonomy in parts of Turkey for more than two decades, a conflict that has cost tens of thousands of lives, and its fighters have bases in Kurdish sections of northern Iraq.
Turkey faces domestic pressure to strike back at the rebels, and the U.S. and the European Union consider the PKK a terrorist organization.
But the U.S. opposes any large-scale Turkish incursion into northern Iraq, currently one of the war-torn country's most stable areas. The more limited raids conducted recently, including Wednesday's, nevertheless put Washington in an awkward position because Turkey and Iraq are both key U.S. allies.
President Abdullah Gul said Wednesday that Turkey was pleased with U.S. cooperation, including the sharing of intelligence. "It is a cooperation that befits the allies," he was quoted as saying by the state-run media.
But Gul also appeared to bemoan that the cooperation started recently. Turkey, a NATO ally, has long complained of U.S. inaction against the Iraq-based rebels.
"It's how it should have been," Gul said. "We could have arrived at this point much earlier."
Inside Turkey, troops said they killed six rebels in the second day of operations on the slopes of Mount Gabar, near the Iraqi border.
Oil prices jumped Wednesday on supply concerns stoked by the new round of Turkish airstrikes in northern Iraq and a growing belief that domestic oil inventories fell last week.
The Turkish military, which relies on fighter jets and artillery units to hit rebel targets miles away from the border, has vowed to keep up its attacks on the rebels regardless of weather in snowy northern Iraq.
On Tuesday, Turkey's military claimed that more than 200 Kurdish rebel targets in northern Iraq have been hit since Dec. 16, killing hundreds of rebels.
Asked about casualties, Maj. Gen. Kevin Bergner, a U.S. military spokesman in Baghdad, said that Turkish forces "are in this case the arbiters of ground truth."
The rebels traditionally withdraw to their hide-outs during winter when snow hampers their movement in the mountains, then intensify their attacks on Turkish targets in the spring.
Snowfall in the mountains along the Iraqi and Turkish borders has made access to the area difficult, although a full-blown winter onslaught has yet to hit the area.
In Istanbul, the city's mayor said traditional New Year celebrations at a main square were canceled out of respect for soldiers killed in recent PKK attacks and those currently fighting the rebel group.
"We had made preparations for Taksim Square; however, we have so many martyrs," Topbas told reporters. "At this moment in the southeast region, we have soldiers fighting in the mountains in terrible weather."
Despite freezing temperatures, Turkish commandos in white snow overalls comb the rugged terrain every day in hunt of rebels.