Security alert was raised in Davao City and Cagayan de Oro because of a potential terrorist threat.
That threat involves Abdul Basit Usman a bomb-making expert with links to the Abu Sayyaf, thought to have been killed by a US drone attack in Afghanistan back in 2010.
No less than President Aquino warned Davao Mayor Rodrigo Duterte about the threat, prompting Duterte to place his city on heightened alert.
Duterte also banned weapons from being brought into Davao. – ANC World Tonight, June 28, 2014