DUBAI, Oct 16 (Reuters) - Iranian naval forces intervened on Saturday to repel pirates who attacked an Iranian oil tanker in the Gulf of Aden, Iran"s state media reported. Pirates in five speedboats attacked the unidentified tanker, but they fled after facing heavy fire from Iran"s navy, the state broadcaster IRIB said on its website. Iran’s navy has extended its reach in recent years, dispatching vessels to the Indian Ocean and the Gulf of Aden to protect Iranian ships from Somali pirate attacks.