Section 1. Section 3 of Presidential Decree No. 1866, as amended, is hereby further amended to read as follows:

"SEC. 3. Unlawful Manufacture, Sales, Acquisition, Disposition, Importation or Possession of an Explosive or Incendiary Device. — The penalty of reclusion perpetua shall be imposed upon any person who shall willfully and unlawfully manufacture, assemble, deal in, acquire, dispose, import or possess any explosive or incendiary device, with knowledge of its existence and its explosive or incendiary character, where the explosive or incendiary device is capable of producing destructive effect on contiguous objects or causing injury or death to any person, including but not limited to, hand grenade(s), rifle grenade(s), 'pillbox bomb', 'molotov cocktail bomb', 'fire bomb', and other similar explosive and incendiary devices.

"Provided, That mere possession of any explosive or incendiary device shall be prima facie evidence that the person had knowledge of the existence and the explosive or incendiary character of the device.

"Provided, however, That a temporary, incidental, casual, harmless, or transient possession or control of any explosive or incendiary device, without the knowledge of its existence or its explosive or incendiary character, shall not be a violation of this Section.

"Provided, further, That the temporary, incidental, casual, harmless, or transient possession or control of any explosive or incendiary device for the sole purpose of surrendering it to the proper authorities shall not be a violation of this Section.

"Provided, finally, That in addition to the instances provided in the two (2) immediately preceding paragraphs, the courts may determine the absence of the intent to possess, otherwise referred to as 'animus possidendi', in accordance with the facts and circumstances of each case and the application of other pertinent laws, among other things, Articles 11 and 12 of the Revised Penal Code, as amended."