Eccentric, strange CIA apprehension causes dangerous stoppage (7,6)
I believe the answer is:
cardiac arrest
'dangerous stoppage' is the definition.
'cardiac arrest' can be an answer for 'stoppage' (someone's heart stopping). I am not sure about the 'dangerous' bit.
'eccentric strange cia apprehension' is the wordplay.
'eccentric' becomes 'card' (card can mean an eccentric person).
'strange' is an anagram indicator.
'apprehension' becomes 'arrest' (synonyms).
'cia' with letters rearranged gives 'iac'.
'card'+'iac'+'arrest'='CARDIAC ARREST'
'causes' is the link.
Can you help me to learn more?
(Another definition for cardiac arrest that I've seen is " Stoppage of the heart".)