Possible Clues:

• Wise to include wrecked boat in malicious damage
• Don't go away, Sister, by the sound of it; there's no bloody flow (6)
• No progressive state succeeded with secret police
• Spying's beginning thanks to MIsix inactivity
• Stagnation, or stoppage of circulation
• 'Don't go and sound stagnated, little sister (6)'
• Arrest by secret policemen
• Sister sat back in a state of equilibrium
• Possibly assist when blood circulation is arrested
• Stagnation