A Turkish air force jet has gone down in Syrian waters, but Turkey's prime minister said he could not confirm media reports that it had been shot down by Syrian forces.
Turkish and Syrian vessels were searching for the plane - which the media identified as an F-4 - and its two pilots, prime minister Recep Tayyip Erdogan told a televised news conference.
Turkey has joined nations in saying that Syrian president Bashar Assad should step down because of the uprising in his country that has killed thousands of people.
Turkey has also set up refugee camps on its border for more than 32,000 Syrians who have fled the fighting. That situation generated media speculation about what the Turkish plane was doing over Syrian territory and whether Syria had shot it down, then apologised.
"I cannot say it was downed, without definite information. It is not possible to say that," Mr Erdogan said of the plane. He also said he could not confirm that Syria had apologised.
The prime minister held his news conference after returning from a visit to Mexico and Brazil.
Mr Erdogan confirmed that the plane went down some eight miles from the Syrian town of Latakia over the Mediterranean Sea. "Four of our gunboats and some Syrian gunboats are carrying out a joint search there," he said.
Mr Erdogan, citing lack of information, said he could not say why the Turkish plane was flying in that area. He said a detailed statement might be issued later following a security meeting with Cabinet ministers and military leaders. The meeting was originally called to discuss intensified Kurdish rebel attacks in Turkey.
In Lebanon, Hezbollah's Manar TV reported that Syrian forces shot down the Turkish plane, citing unidentified Syrian security sources. Hezbollah is closely allied with Syria. The report could not be confirmed.
The Turkish jet disappeared south-west of the Turkish province of Hatay, which borders Syria, Governor Ulvi Saran of the southern province of Malatya told Turkey's state-run Anadolu Agency. He said it had taken off from a military air base in Malatya.