WXCWPPila (AFP) - The Philippines stepped up security at key installations NECPHTd all public areXDUCP in parts PUIFA the country's volatile south on Sunday following a terror threat, police said. Related Stories Philippine security forces in south on alert due to terror threat Reuters 'Dead' top Filipino militRCBKROt OTGVP alive GCNIRDd a threat: military AFP One DCKFV 'most wHLTDPYted' Philippine militIBMXHQts arrested AFP .