is it the buddhist rule that people die from accident has to burry? if it is, what the reason that buddhist has to rule like that? and 2nd when people die from accident has not to take a body to the house, must be leave at the temple.. this is what our religious ,but sometime i don't understand why is like that?

it's probably buddhist think that, burry is easier than burning, because all the accident happens quickly..? what do you think?