The investigation into the two improvised explosive devices (IEDs) found underneath lawyer-activist Siti Kasim's car last month has reached a dead end.

Former Kuala Lumpur police chief Mohd Shuhaily Mohd Zain - who is being promoted to a federal position - said several CCTV camera recordings of the case did not show any potential suspects near Siti's car.

"We also did not find any fingerprints...