The explosion in male' was caused by a simple homemade IED device that used atrigger combined with washing machine timer and a mobile phone.
Components:
- Nokia 1110
- Washing machine timer
- Detonator Circuit
- 9V Battery and Clip
- Detonator
- Lighter gas can
The mobile phone used in the device is a Nokia 1110. The phone have two easy options to use as a trigger for the detonator circuit. One option is to use the connections to the phones vibrating motor. This connection provides a voltage of 3v when the phone is ringing.
The other option is to connect the detonator circuit to the phones ring speaker.
Washing Machine Timer
Once the device is armed, the device is ready to explode even for a false ring to the mobile number. To prevent this the washing machine timer is used. The washing machine timer usually have a delay of 15 - 20 mins. The timer provides a safe exit time of 15 mins. Once the washing machine timer is finished ticking then the circuit is completed for the detonator.
Detonator Circuit
The detonator circuit probable was powered by the 9V Battery. The main component would be a transistor to trigger the circuit on reception of a voltage from the mobile device to the transistor base.
Detonator
Detonator could be a wire from a small bulb or a single strand of thin copper wire. This wire could have been inserted into a paper tube of gunpowder from match sticks. Once the 9V is applied to the wire, the wire becomes red hot and ignites the gun powder and providing enough explosive power to ignite the lighter gas can.
Lighter Gas Can
The Lighter gas can was the main fuel in the explosion as is proved by the burn injuries of the victims. For make it more lethal hundreds of nails was used. These nails was probable wrapped around the can using paper that is visible in the picture above.
Conclusion
In concluding the analysis, the device is not very technically sophisticated. But the maker of the circuit and the detonator device must have a fair knowledge of electronics and chemistry. It is a work done by some amateurs. Any body who have access to the internet could have made a more powerful explosive with a more sophisticated detonating device with a digital timer.
Note: I have tried my best not to reveal the technical knowhow for such a device.
