( AP ) - An Iranian air force F-4 Phantom jet crashed into the Oman Sea on Monday off the southeastern coast of Iran, the official news agency IRNA reported.
The semiofficial Fars news agency said the fate of the pilot and the cause of the crash were still unknown.
IRNA said the jet, belonging to the army air force, into the sea near the port of Konarak.
During the pro-Western rule of Shah Reza Pahlavi, Iran's air force was considered the best-equipped in the region and operated some of America's most capable aircraft.
But following the installation of an Islamic regime in 1979, relations quickly soured and resulted in a U.S. arms embargo that remains in effect.
Left without spare parts during the 1980-88 Iran-Iraq war, Iran's air force had to keep its planes flying by cannibalizing other jets.
Although Iran has purchased an unspecified number of Russian-made Sukhoi fighter jets in the past two decades, experts agree that the bulk of its air force is still made up of Vietnam War-era F-14s, F-4 Phantoms and F-5s.
Iran, seeking to bolster its air defenses amid rising tensions over its nuclear program, has turned to Russia and China for the warplanes needed to replace its obsolete U.S. jets.
Both Moscow and Beijing refuse to comment on reports in the Israeli and Russian media, along with Western aviation publications, that Iran aims to order Russian Sukhoi Su-30 and Chinese Chengdu J-10 combat aircraft.
More recently, Iran has tried to develop its own indigenous manufacturing capability. The Saegeh, or Thunderbolt, light fighter, which appears based on the old U.S. F-5, has recently come off the production line.