Is it permitted to bury someone at sea?
I think it might be since voyages can be very long and if someone dies then it might not be possible to wait until the the ship reaches land.
If it is permitted, what are the Islamic teachings and rules regarding it?
Is the usual cloth Kafn used or a coffin is needed? Do they simply throw the body into the sea or is it weighed down by something? Are their any instances of the companions of the Prophet getting buried at sea? Is there any special dua or Janaza etc.