Turkey was weighing its response Saturday to the shooting down by Syria of one of its planes, an incident that sent tensions soaring between two neighbors already at odds over the uprising against President Bashar al-Assad's rule.
The deliberations appeared to be focusing in part on the question of whether the Turkish plane was in Syrian airspace when it was hit, as the Syrian government claims. Two pilots remained missing late Saturday, and the Turkish and Syrian navies had launched a massive rescue operation in the eastern Mediterranean, where the aircraft came down.
Turkish President Abdullah Gul was quoted by Turkish news media as saying the government was trying to ascertain where the plane was when the incident occurred Friday, suggesting it was looking for ways to ease the crisis.
Gul warned, however, that Turkey is not prepared to let the shooting pass without response. He said that even if the Turkish plane had briefly strayed into Syrian airspace, such events were "a little bit routine" along the two countries' 566-mile border.
"It is not possible to cover over a thing like this," the state news agency Anatolia quoted him as saying. "Whatever is necessary will be done."
Turkish media initially reported that the plane was a U.S.-made F-4 fighter jet, but some reports Saturday suggested it may have been a reconnaissance aircraft.
The shooting presented Turkey with a dilemma at a time when an effort to aid the rebel Free Syrian Army is gearing up along its border with Syria, in collaboration with Saudi Arabia, Qatar and the United States.
A conflict with Syria now could rapidly spiral into a regional war, since under the charter of NATO, to which Turkey belongs, Turkey can call on alliance members for support in the event of an attack. Yet few in the international community have expressed any appetite for military intervention.
Turkey recalled all of its diplomats from the Syrian capital, Damascus, months ago, in just one sign of how far the two countries' once warm relationship has deteriorated since the Syrian uprising erupted in March last year.
Several Turkish government officials urged restraint. "We must remain calm and collected," Deputy Prime Minister Bulent Arinc said, according to the Associated Press. "We must not give premium to any provocative speeches and acts."
The shooting came a day after the defection to Jordan of a Syrian pilot, who flew his MiG-21 fighter jet across Syria's southern border and sought political asylum.
The defection prompted speculation that Syria's air defense forces may have been on alert for -- or seeking to deter -- further defections.
Syria's account of the incident, however, claimed that the gunners who opened fire at the plane did so because it was approaching Syrian territory and they regarded it as a threat. The official news agency SANA said the plane was flying over the sea toward the Syrian coast at high speed and low altitude when it was shot down.
Syrian Foreign Ministry spokesman Jihad Makdissi has sought to play down the incident, stressing on his Twitter account and in an interview with a Turkish television station that Syria was responding to a perceived threat and had since joined in the search for the missing pilots.
"There was no hostile act against Turkey whatsoever," he told the A Haber TV network Saturday. "It was just an act of defense for our sovereignty."