Police have charged a man with conspiracy to murder and firearms offences after a gun was recovered from a car in which he was travelling.
Officers investigating suspected dissident republican activity found the weapon after stopping the vehicle outside Cookstown on Monday.
The 30-year-old is also charged with possession of a firearm with intent and possession of ammunition.
There other men have already been charged over the gun find.
They were charged on Wednesday with possession of a gun and possession of ammunition.
The man charged on Friday is also accused of having articles in his possession for the purposes of terrorism.
He is expected to appear in court in Omagh on Saturday.
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