MANILA, Philippines - In a shocking incident on Monday morning, a street sweeper is said to have reported a suspicious, possible explosive found in a trash bin merely 200 metres from the U.S. Embassy in Manila.

The Philippines police and the country’s bomb squad rushed to the U.S. Embassy in the southbound lane of Roxas Boulevard and found the suspected “improvised explosive device” in the trash bin and subsequently detonated the device. 

Speaking at a press conference post the detonation, National police chief Director-General Ronald dela Rosa declared that the incident was an "attempted act of terrorism" and that investigators were trying to find out if Maute militants could have been behind the placement of the bomb. 

Further, the police revealed that the improvised bomb was made from an 81-mm mortar round, cellphone, blasting cap and a small battery - similar to bombs used by the extremist group that has links with Islamic State, Maute group and has previously been linked to the attack in Davao city that left 14 people dead in September this year. 

Manila Police District head Senior Superintendent Joel Coronel assured citizens, “There is no danger, there is no cause for alarm...The blast you heard was caused by ... a controlled detonation. We are trying to identify who left the package at the trash bin.”

Meanwhile, indicating that investigators are looking at establishing a possible link between the two attacks, Dela Rosa said, “Unless we get hard evidence, by analysis we can theorize this can be linked to Maute because of what happened in Davao.”

The device detonated on Monday is said to have been powerful enough to kill people within 100 meters (110 yards), officials revealed, while confirming that no injuries were reported from the incident as the area had immediately been cordoned off. 

He further stressed that as a response to the incident on Monday, the country would be placed under more tighter security, adding, “We will ask mall authorities to also heighten security. We may revive checkpoints.”

Last week, the country’s military forces began an operation against the Maute group, which is suspected to have been behind September’s deadly bombing in Davao city, which in President Rodrigo Duterte's home town.

Reports further revealed that militants were seeking shelter in an abandoned government building in Butig town, which is a Muslim rural town on Mindanao island. 

Philippine troops, backed by bomber aircraft, were said to have been engaged in heavy artillery firing to drive the militants out of the building.

Dela Rosa said, “"Because of an ongoing police/military operation there, [the militants] have many casualties. We can theorise that this is a diversion to loosen our operations.”

Authorities were also reportedly probing to establish any possible links that would lead to involvement of another ISIS-sympathizing southern group, the Ansar Khilafa Philippines. 

The southern Philippines region is home to many extremist groups and a four-decade Muslim separatist revolt that has so far left more than 100,000 people dead.

Meanwhile, the U.S. Embassy spokesperson Molly Koscina issued a statement confirming that a municipal employee had reported the discovery of a “device” to embassy guards. The guards are said to have contacted the local police. 

In the statement, she said, “We are thankful that the municipal employee and the PNP took quick and appropriate action to ensure the safety of all.”