Note the way the subject changes abruptly from "they were afraid" to "Now when Jesus was risen". In Greek, "for they were afraid" is εφοβουντο γαρ, ephobounto gar, literally "they-were-afraid because". This is very odd Greek. Like its Latin equivalent enim, the Greek conjunction γαρ, gar, means "because" and takes second place in a sentence or clause. It almost never ends a sentence in this way and this is, indeed, the only example in the whole of the New Testament. In the rest of Mark, for example, gar is used in the conventional way:
The suggestion is, then, that part of the original manuscript was lost or incomplete after 16:8, and that a later hand added 16:9-20, describing appearances by the resurrected Christ in a different style and using a different Greek vocabulary. Skeptics have therefore used the argument from silence to suggest that resurrection appearances and the virgin birth were not present from the beginning in Christianity, because neither is mentioned in Mark, the earliest Gospel.
See also: Gospel of Mark
For and against the authenticity of Mark 16:9-20 (http://www.bible-researcher.com/endmark.html)
wikipedia.org dumped 2003-03-17 with terodump