TAIPEI/BEIJING, Feb. 7 -- Rescue workers recovered another five bodies from the Keelung River in Taipei on Saturday, three days after the TransAsia Airways plane crash that killed at least 40.

Three passengers were still missing.

There were 15 survivors. Thirty-one tourists from the Chinese mainland who had just completed visits to Taiwan were on board the plane bound for Kinmen when the tragedy happened and at least 26 of them have died in the crash.

Rescuers found the bodies in waters 500 meters, 600 meters and 1 km downstream from the crash site, according to Taiwan's disaster response center.

A public memorial ceremony has been scheduled on Feb. 10 in Taipei to mourn victims of the crash.

The ATR72-600 turboprop passenger plane crashed into the Keelung River in Taipei shortly after takeoff from Songshan Airport at 10:52 a.m on Wednesday.

The exact cause of the crash remains unclear but initial analysis of the flight data recorder and the cockpit voice recorder by the Aviation Safety Council showed the right engine of the plane flashed a warning signal just 37 seconds after takeoff and pilots manually cut the fuel supply to the left engine, leading to a loss of power in both engines before the plane went down.

Thomas Wang, managing director of the ASC, said the pilot announced a "flame-out", which can occur when the fuel supply to the engine is interrupted or when there is faulty combustion. However, Wang said there was in fact no flame-out, and the engine on the right side had shifted into idle mode without any change in oil pressure.

The 72-seater aircraft, an ATR 72-600 manufactured by Franco-Italian firm ATR, is able to fly or take off with just one functioning engine, said Yann Torres, of France's aviation accident investigation bureau (BEA) who has joined the investigation.