Egypt's air accidents chief said on Thursday that a vessel provided by French company ALSEAMAR, which specializes in marine wreckage searches, will join within hours the hunt for the black boxes from crashed EgyptAir flight MS804. Ayman al-Moqadem said negotiations were also underway to contract a second firm to help in the search. A week after the Airbus A320 crashed into the Mediterranean with 66 people on board, including 30 Egyptians and 15 from France, investigators have no clear picture of its final moments. Search teams are working against the clock to recover the two black box flight recorders that will offer vital clues to investigators, because the pingers that help locate them in deep water cease working after about 30 days.