CAIRO: The head of Egypt’s forensics authority dismissed a suggestion on Tuesday that a small size of body parts were retrieved since the EgyptAir crash last week indicating that there was an explosion on board. Investigators struggling to work out why the Airbus 320 jet vanished from radar screens last Thursday, with 66 passengers and crew on board, are looking for clues in the human remains and debris recovered from the Mediterranean Sea so far. The plane and its black box recorders, which could explain what brought down the Paris-Cairo flight as it entered Egyptian air space, have not been located. An Egyptian forensic official said that 23 bags of body parts have been collected since Sunday, the largest of them no bigger than the palm of a hand. The official, speaking on condition of anonymity, said that their size suggested there had been an explosion although no trace of explosives had been detected. However, Head of Egypt’s forensics authority Hisham Abdelhamid, said that all assessments were “mere assumptions” and that it was too early to draw any conclusions. At least two other sources with direct knowledge of the investigation also said it would be premature to say what caused EgyptAir flight 804 to plunge into the sea. French investigators say that the plane sent a series of warnings indicating that smoke had been detected on board as well as other possible computer faults shortly before it disappeared. The signals did not indicate what may have caused the smoke, and aviation experts have said that neither deliberate sabotage nor a technical fault could be ruled out. Investigators rely on debris, bags and clothes as well as chemical analysis to detect the imprints of an explosion, according to people involved in two previous probes where deliberate blasts were involved. An Egyptian team formed by the Civil Aviation Ministry is conducting the technical investigation and three officials from France’s air accident investigation agency (BEA) have also been in Cairo since Friday, with an expert from Airbus to assist. Egypt has deployed a robot submarine and France has sent a search ship to help hunt for the black boxes but it is not clear whether either of them could detect signals emitted by the flight recorders, which are lying in waters possibly 3,000 meters deep.