One article notes that Mahmoud Abbas and Mohammed Dahlan were fighting to become Arafat's successor and therefore one of them must have been involved. It also says that Abbas has the results of an investigation that determined the killers but refuses to release it.
A second article quotes former director of the PA's General Intelligence Service, Fahmi Shabana, as saying that Abbas was involved in the assassination.
A third says that Arafat advisor Bassam Abu Sharif claims that one of the members of the Arafat assassination team escaped with the help of the PA and now lives in the Ukraine in luxury.
It is nearly impossible to find any Palestinian who does not think Arafat was assassinated, despite a Russian study and French report that found no evidence he was poisoned by polonium and numerous debunkings of the Swiss study that suggested it as a possibility.
Conspiracy theories are more fun.