New Delhi, Sep 15 (PTI): The families of those on board the missing AN-32 aircraft of the IAF have been informed that their relatives are "presumed dead" as the search operations for the ill-fated aircraft continued.

There were 29 people on the transport plane which had vanished over the sea after it took off from Chennai for Port Blair on July 22.

"The Court of Inquiry, upon very careful scrutiny of the circumstantial evidence available and in light of extensive search and rescue operations carried out, has concluded that it is unlikely that the missing personnel on board the ill-fated aircraft would have survived the accident.

"It is with a feeling of profound sadness that the Court of Inquiry has recommended that your son/daughter be presumed to have been fatally injured," read the August 24-dated letter from Indian Air Force to the families of those in the aircraft.

IAF sources said the families have been given the information so that they can go ahead with insurance and other administrative formalities.

The letter came annexed with a certificate of presumption of death.

"The search for missing AN32 is still in progress," defence sources said.

The plane did not have an underwater locator system, which has made the search difficult.

"No fewer than 201 search and rescue sorties, using all suitable aircraft at our disposal were undertaken. Approximately 2,17,800 square nautical miles (Sq Nm) have been covered multiple times by these aircraft," the letter stated.

"International emergency response teams and satellites from USA also did not help in getting any concrete information about the missing aircraft," it added.