ZAMBOANGA CITY -- Security at all airports and terminals in the country were placed Friday on heightened alert status following the bombing incident in this city that killed two people and wounded 24 others.

The Civil Aviation Authority of the Philippines (Caap), at the same time, has ordered all airport security offices to coordinate with the Philippine National Police (PNP) and Armed Forces of the Philippines (AFP) that were tasked by President Benigno Aquino III to identify the brains behind the Zamboanga airport bombing.

The orders came despite the PNP's assurance that there will be no spill over of such atrocity in Metro Manila and other parts of the country. The police described Thursday's bombing in Zamboanga as an isolated incident, and authorities are looking at it as politically motivated.

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Sulu Governor Abdusaakur Tan, who was wounded in the incident, believed he was the target of the bombing, citing several attempts on his life in the past years.

Tan was coming out of the arrival area around 6:15 p.m. Thursday after disembarking from a commercial plane that arrived from Manila when a bomb kept inside a bag of Reynaldo Apilado, who was earlier suspected as suicide bomber, exploded just a meter away from him. Apilado, who was carrying the bag, was killed in the blast.

A special task group is now conducting investigations on the incident, while security forces in this city, as well as in the cities of Cebu, Iloilo, Cagayan de Oro, Davao and Metro Manila are on heightened alert status.

PNP Director General Jesus Verzosa, who arrived in this city Friday morning to oversee the investigation, said they will do everything to determine the people behind the bombing.

Western Mindanao Command Chief Ben Dolorfino said they have deployed additional troops in populated areas like transport terminals in Zamboanga to prevent a repeat of the latest bombing incident.

"Immediately after the explosion last night (Thursday night), we heightened checkpoint operations, both by the AFP and PNP, and then we have hardened other areas where such incidents may occur," he said.

Colonel Santiago Baluyot, commander of the military's Task Force Zamboanga, said at least 100 personnel were sent to the streets to ensure peace and order apart from police augmentation force.

"We will tighten, further tighten security and importantly intelligence should be further strengthened," said AFP spokesman Jose Mabanta.

In Iloilo, security was also tightened after the Caap office received a call saying two grenades were set to be exploded inside the Iloilo Airport in Cabatuan town.

Superintendent Vicente Armada, chief of the Police Center for Aviation Security (PCAS), said the call was received by a security guard around 11 a.m. Friday.

The grenades, he said, were allegedly placed near the airport's arrival area. An Explosive and Ordnance Division team that was sent to conduct search, however, did not find any explosive device.

Police authorities believe that some passengers could have been behind the bomb scare, saying several people are protesting the sudden transfer of the airport's arrival area.

In Cebu, policemen were also deployed to Mactan Cebu International Airport in Lapu-Lapu City since Thursday night to beef up security, particularly at the arrival and departure areas of the airport.

The "No ID, No Entry" policy was also implemented to control the people at the airport, and all baggage are subject to checking to make sure that no explosives can enter the airport's premises.

Superintendent Solito Salcedo Jr. of PCAS said they monitor people who are entering and exiting the airport since Thursday night.

At Davao International Airport in Davao City, security was also tightened in the area outside the terminal building, as well as in the baggage checking before people can enter the building.

Davao City Mayor Sara Duterte also called for a command conference at the Public Safety Command Center on Thursday night to review the city's security plans during a bomb threat.

"Sa ngayon, we have checkpoints and continued police and military visibility. Considering na malapit na ang Kadayawan festival the police and military have (intensified) security measures in the city," Duterte said.

The same security measures have been implemented in Cagayan de Oro City, with police and military personnel deployed to monitor in and outside the city's airport.

The Manila International Airport Authority (MIAA) and Philippine Airlines (PAL) in Metro Manila have also beefed up security.

Jose Angel Honrado, MIAA general manager, said in an interview that they have deployed 18 bomb sniffing dogs in the three terminals of the Ninoy Aquino International Airport (NAIA).

PAL, meanwhile, deployed additional exclusive K9 units at the NAIA Terminal 2 while assuring the public of normal operations at the Zamboanga airport.

"We made this measure to put up a security blanket in the country's main airport. We also raised a red alert level in the airport," Honrado said.

The government, amid the heightened alert status, assured the public that law enforcers are doing their best to keep the people safe.

Presidential spokesperson Edwin Lacierda said Defense Secretary Voltaire Gazmin and Local Government Secretary Jesse Robredo are on top of the situation.

"Instructions were already given to them," he said.

Presidential Communications Group official Ricky Carandang, meanwhile, dismissed that the bombing was a destabilization attempt against the new administration.

"It's too early to say. They have not completed the investigation. We will not discount anything at this point. But it might be a bit too speculative at this point to say that this is an event to destabilize the government," he said.

As of this posting Friday, authorities handling the investigation on the Zamboanga airport bombing are reviewing the content of the closed-circuit television camera that was installed at Zamboanga International Airport to see how the incident actually happened.

Mayor Lobregat said PNP Director Verzosa has ordered the local police to enhance the video, which was not clear, for proper review.

He also said that majority of the bombing victims were already discharged from the hospitals in this city. Nine of the 24 wounded, however, still remain at the hospitals. Two of them are in critical condition.

Lobregat said the City Government will shoulder the hospitalization expenses of the victims. (Bong Garcia/Jill Beltran/Virgil Lopez/VR/FP/JCZ of Sun.Star Davao/PNA/Sunnex)