Police have defused an explosive device on a main road near the United States embassy in Manila.
Philippine police chief General Ronald De la Rosa said the bomb scare could have been the handiwork of Islamic militants.
The device was found as Manila police responded to a call about a "suspicious package" in a rubbish can. The nearby US embassy was evacuated and parts of Roxas Boulevard were closed for two hours during rush hour, causing major traffic snarls.
The police said the device included an 81-mm mortar, battery, mobile phone, a switch device and a blasting cap.
"The (device) found near the US embassy today has the same design as the one used in the Davao market blast," De la Rosa said in a press briefing, referring to the a September explosion that killed 15 in the night market in Davao City.
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Three members of the Maute terrorist group were arrested for the Davao attack.
De la Rosa expressed the possibility that the bomb threat was a "diversionary tactic" by the Maute terrorist group, which is now battling military troops after it occupied the town centre of Butig in Lanao del Sur in the country's south.
The US embassy said a municipal employee discovered the device and told embassy guards who then contacted the police.
"We are thankful that the municipal employee and the (police) took quick and appropriate action to ensure the safety of all," US Embassy Press Attache and First Secretary Molly Koscina said in a statement.
