Manila: Authorities on Thursday recovered an improvised explosive device (IED) in Bulacan, nearly two weeks after another bomb placed near the US Embassy last was discovered.

According to National Police Director General Rolando dela Rosa, Mohammad Jumao-as, an X-ray technician, led authorities to where the bomb was hidden at an area in the village of Santa Ana, in the town of Bulakan in Bulacan province in Central Luzon on Wednesday.

The discovery of the IED came after police arrested on Thursday Jumao-as’ alleged accomplice in the November 28 planned bomb attack at the US Embassy. Authorities refused to identify the co-conspirator by name, but said he was arrested in a police operation conducted in Zambales in Central Luzon.

Dela Rosa said the IED was made from a 105mm howitzer round rigged to a mobile phone devise for remote detonation.

“The IED is capable of causing destruction within a 50 to 80 metre radius from the site of the blast and has the potential of causing death and injury to as many as 300 people,” said Dela Rosa.

The IED was deactivated by police using a water cannon disruptor.

Bombs fashioned from undetonated artillery shells are typical in Central Mindanao area where unexploded ordnance left in the battlefield are used by some groups in carrying out terror attacks and extortion. In Maguindanao and North Cotabato, unexploded artillery shells are collected and sold as improvised bombs.

In Metro Manila and Central Luzon where the devices were found, the discovery of such objects are unusual since there are no military operations conducted anywhere near where unexploded shells can be collected.

Dela Rosa said the IED placed near the US Embassy November 28 is similar to that which caused the September 4 explosion at a night market in Davao City that killed 15 people.

The arrest of Jumao-as and another suspect in Zambales bring to four the number of “persons of interest” in the foiled US Embassy bombing.

Last December 1, authorities in Manila and Central Luzon arrested Jiaher Guinar, 30, and Rayson Kilala, aka “Rasid,” suspects in the alleged plan to bomb the US Embassy in Manila.

Guinar, a native of Marawi City, was arrested in Caloocan City’s Bagong Silang district, while Rasid was apprehended in the village of Bagong Bayan in Bulakan.

At around 6:50am on November 28, an ED was found inside a trash can placed on a roadside about 200 meters from the US Embassy.

Authorities have come up with possible suspects, both from groups based in Mindanao, the Ansar Khalifa Philippines (AKP) which operates in Southern Mindanao region and the Maute Group which is based mainly in Lanao. Both however, profess allegiance to Daesh.

Dela Rosa said that during a debriefing police conducted on Guinar and Rasid, the two claimed that they were affiliated with the AKP.