Military operation
The 2008 Turkish incursion into northern Iraq, code-named Operation Sun () by the Turkish Armed Forces, began on February 21, 2008, when the Turkish Army sent troops into northern Iraq to target the Kurdistan Workers' Party (PKK). The ground offensive was preceded by Turkish Air Force bombardments of PKK camps in northern Iraq, which began on December 16, 2007. It was the "first confirmed ground incursion" of Iraq since the 2003 U.S.-led invasion.
Initial reports indicated that up to 10,000 troops had taken part in the operation, although the Kurdistan Regional Government and the Multi-National Force – Iraq claimed only a few hundred troops were involved.
Background.
In October 2007, Turkish jets and ground forces clashed with PKK forces in Turkey and over the border into northern Iraq.
Winter bombing campaign.
Turkey launched its first cross-border raid on December 16, 2007, involving 50 fighter jets. A Turkish military statement said that up to 175 militants were killed on that day alone, while Iraqi officials reported that the strikes had targeted 10 villages and killed one civilian. The PKK reported seven deaths.
On December 26, the Turkish General Staff said Turkish military aircraft bombed eight PKK bases in northern Iraq in a raid undertaken after "it was determined that a large group of militants, who have been watched for a long time, were preparing to pass the winter in eight caves and hideouts in the Zap region," the statement said.
On January 10, 2008, Turkish warplanes bombed PKK hideouts in northern Iraq, the military announced, but there were no reports of casualties or serious damage.
The Turkish military said in a statement on February 4 that Turkish fighter jets struck nearly 70 PKK targets in northern Iraq in a series of strikes.
The president of Kurdish region of northern Iraq, Massoud Barzani, condemned Turkey's raids and warned Ankara to stop the strikes, and the Iraqi Foreign Minister Hoshyar Zebari, who is a member of the Kurdish Democratic Party (KDP), expressed concern that "unilateral actions" could harm Iraqi and Turkish interests. According to the Turkish General Staff's estimates, there were 300 PKK militants in the region prior to the incursion and the General Staff claims that 240 militants were killed.
Operation Sun.
Preparation for the ground incursion.
On February 21, Turkey began targeted artillery and aerial bombardment of PKK positions in northern Iraq in order to "destroy the organizational infrastructure in the region." This lasted from 10:00 to 18:00 local time. The Turkish government reported that on the day of the operation, Turkish President Abdullah Gül made a telephone call to Iraqi President Jalal Talabani, himself a Kurd, to brief him on the details of the incursion. He also invited Talabani to come to Turkey.
Turkish Prime Minister Recep Tayyip Erdogan said he called Iraqi Prime Minister Nouri al-Maliki on the night the ground operation began, and later U.S. President George W. Bush. The United States was guarded in its response to the incursion, requesting that Turkey take care to only target the PKK, to "limit the scope and duration of their operations," and to work with Iraqi and Kurdish officials.
Incursion.
The incursion itself began at 17:00 UTC February 21, 2008. Reports from NTV Turkey indicated that 10,000 troops were involved in the operation, and had advanced 10 km beyond the Turkish border into Iraq, mainly around the Hakurk region. Another report from CNN-Turk said that 3000 special forces were involved.
The incursion was announced on the Turkish General Staff's website the following day, and would constitute the "first confirmed ground incursion" since the 2003 invasion of Iraq.
According to the Iraqi Foreign Minister, Turkish troops had advanced only 5 km into Iraqi territory. 60 tanks were also said to have initially entered Iraq, but by the following day some had returned across the border.
Kurdish-Iraqi peshmerga forces were put on alert and prevented Turkish military monitors in northern Iraq from leaving their camps.
Iraqi officials announced that no Turkish troops had crossed the Iraqi border using the major land route into Iraq, the Khabur Bridge, and there were no reports of Turkish contact from the Kurdistan Regional Government Peshmerga forces. Iraq claimed that Turkey had destroyed five bridges in the area.
On February 24, PKK sources claimed that PKK fighters had shot down a Turkish Cobra helicopter and Turkey confirmed this later in the day, saying that the incident happened "due to an unknown reason." Advancing Turkish troops were attacking the PKKs' shelters, logistic centers and ammunition. According to Turkey, the retreating PKK militants set booby traps under the corpses of dead comrades and planted mines on escape routes in order to gain time. 
By February 25, the military had advanced more than 30 km (20 miles) into Iraq and claimed to have destroyed seven militant camps. Heavy fighting raged at the entrance to the Great Zab valley with most of the Turkish troops inside Iraq involved in an attack on a key PKK command centre in the valley after taking control of the PKK's Haftanin camp about 5 km (3 miles) from the border. Fighting was concentrated on a strategic hill controlling the entrance to the valley. At least 21 militants were killed in the battle for the hill according to the Turkish army. The PKK used long-range guns to hold off the military, killing two Turkish soldiers, until silenced with light and heavy weapons fire. PKK losses could not be determined because of bad weather.
In the coming days Turkish warplanes bombed PKK hideouts in the mountainous Siladze area and heavy fighting raged in the area near the PKK camps in Zap and Haftanin, with the guerrillas putting up stiff resistance. On February 27 Turkey sent additional troops to Iraq in the face of ongoing pressure from the international community for a speedy withdrawal.
On February 28 a senior Turkish official said Turkish security forces were planning to pull back their troops in a few days to an uninhabited cordon sanitaire on the southern side of the border. Pressure on Turkey to withdraw, however, continued to mount.
The Turkish Army withdrew from Iraq on February 29, declaring that their goals had been achieved and the operation concluded, while also denying that the withdrawal had been prompted by pressure from the United States.
Casualties and losses.
After Turkey withdrew from Iraq, it reported having completed their mission and having killed more than two-hundred PKK militants while also admitted the loss of twenty-seven Turkish soldiers. On the other side the PKK reported the death of over a hundred dead Turkish soldiers and only having lost five militants. Prior to the ground operation, Turkey estimated that an additional 300 PKK militants had been killed by Turkish air strikes which began on December 16, 2007 and continued until the beginning of the ground offensive on February 21, 2008. The number of dead militants denied by the PKK, who claimed they had evacuated the areas before the bombardments. 
Post-conflict operations.
Turkey continued sporadic long-range attacks in the weeks following the operation. In the week of March 24, 2008, Turkey's military announced that it had killed at least 15 rebels in northern Iraq after firing on them with long-range weapons. A spokesman for the Iraqi Kurdish Regional Security Forces, however, denied the report, saying Turkey has not conducted any military operation or air assault there in the previous two weeks.
On April 25 and 26, 2008, the Turkish Air Force bombed the PKK bases in the northern Iraqi regions of Zap, Avasin-Basyan and Hakurk. This was described as the largest attack since the end of Operation Sun. First the T-155 Fırtına howitzers (which have a range between 30 and 56 km, depending on the type of ammunition) were used to shell the PKK positions starting from 18:00 pm on April 25, which lasted for two hours. Then F-16 jets equipped with LANTIRN belonging to the 181st Squadron (Pars Filo) and F-4E 2020 Terminator jets belonging to the 171st Squadron (Korsan Filo) began bombing the PKK's positions in northern Iraq, which lasted 45 minutes. In the meantime, Heron MALE UAVs were used for gaining reconnaissance data regarding the PKK's positions, and about 1000 Turkish commandos entered 8 kilometers into northern Iraq from the border area near Derecik (Şemdinli) in pursuit of the PKK militants. On April 26, 2008, at around 06:00 am, a second aerial strike by the jets of the Turkish Air Force from Diyarbakır Air Base took place, in which the PKK militants using the cemetery area in Hakurk as a hideout were bombed. This was followed by another air strike at 10:00 am in the same morning, during which the Turkish Air Force jets entered 30 kilometers into Iraqi air space.
On May 1, 2008, at least 30 jets of the Turkish Air Force bombed the PKK camps in northern Iraq. The operation began just before midnight and continued into Friday, May 2, 2008. According to Turkish military sources, the PKK targets that were bombed are far from civilian settlements, at the mountains of the Qandil (Kandil) area. On May 3, the Turkish General Staff announced that "more than 150 PKK militants have been neutralized in the latest operation, which targeted the camps in the Qandil Mountains, where most of the high-ranking members of the organization are located." The Turkish General Staff, without giving a precise name, implied that the PKK rebels who were neutralized may also include "a guerilla who leads the organization" as well; leading the Turkish press to speculate that Murat Karayilan might have also been killed during the latest aerial strikes.
References.
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