The official Syrian Arab News Agency (SANA) quoted a regime military official late Monday night who said missiles were fired toward the port city of Latakia from the Mediterranean Sea but were shot down by Syria aerial defense.
The Russian Defense Ministry said in a statement that the Il-20 jet went off radar 35 kilometres away from the coast late Monday (local time) as it was returning to the Russian base near the city of Lattakia.
The ministry also said that it detected missile launches from a French frigate nearby around that time.
The official also said that there were 14 servicemen on board and their fate is unknown.
According to the Russian Defense Ministry, air traffic controllers at the Hmeimim Air Base "lost contact" with the aircraft, during the attack of Israeli F-16 fighters on Latakia.
Syrian state media on September 4 said its air defenses had downed several Israeli missiles in the coastal province of Tartus and in central Hama.
Head of the Syrian Observatory for Human Rights Rami Abdel Rahman told AFP that "violent explosions were caused by missiles targeting ammunition depots in the Technical Industry Institution".
An Israeli military spokesperson when asked about both the reported Israeli strike and the Russian plane said: "We don't comment on foreign reports". The war monitoring group said it was not clear if the depot was for Iranian or Syrian forces.
A Russian military plane with 14 servicemen aboard was accidentally shot down by Syrian air defenses as they tried to repel an alleged Israeli strike on Monday, a United States official told CNN.
While the Russian military said it recorded four F-16 Israeli jets over Syria at the time of the attack on Latakia, the IDF has refused to comment on the report.
Earlier, state media reported another suspected Israeli attack on Damascus's worldwide airport late on September 15.
Erdogan said that the deal "will prevent a humanitarian tragedy that could happen as a result of military action" and that the agreement between the two countries would bring "hope to the region".
Erdogan, meanwhile, told the press conference in Sochi that the biggest threat to Turkish interests in Syria was the presence of the Syrian Kurdish YPG militia, which serves as the main proxy ground force for the U.S. military in taking control of the country's strategically important oil fields in the eastern part of the country.