The Philippine government has beefed up security in Manila this week, after police said they had foiled a plot by suspected Islamic militants to bomb the city. The president, Gloria Arroyo, has warned the country is facing an increased threat from terrorists.
At least eight men have been arrested in the past few days in the Philippines, accused of being members of the Abu Sayyaf, a radical Muslim group blamed for a series of bombings and kidnappings in the south of the country. Some of the men reportedly were found with weapons and bomb materials.
Intelligence services have linked the group to the al-Qaida and Jemaah Islamiyah terror networks.
Family members of two of the suspects strongly deny the pair had links to terrorist groups. The wife of one of the men says her husband was tortured, and evidence was planted on him.
The arrest of four Turkish teachers at a Muslim school in Mindanao has enflamed passions in the Islamic community. The police say they are suspected of having ties to terrorist organizations. But school officials say the men are educators and the arrests a mistake.
The Philippines is primarily Roman Catholic, but has a substantial Muslim minority, concentrated in the southern islands.
In the southern city of Cotabato, Professor Abhoud Lingga heads an Islamic studies institute. He says members of the Muslim community have often been made scapegoats for terrorist acts. He says the government needs to present hard evidence for its claims, or face accusations the arrests were politically motivated.
"If government will fail to file charges against them, and there will be no due process of law, then we might have some reason to suspect that they have other intentions other than really arresting terrorists," he said.
President Gloria Arroyo says the arrests averted bombings of the scale seen in Spain last month, when nearly 200 people died. She is facing a tough re-election battle when Filipinos in May. Terrorism and crime are major issues in the race.
Military officials are convinced the Abu Sayyaf retains the capability to stage bomb attacks. One of the suspects rounded up this week has allegedly claimed to have planted a bomb on a ferry that sank in February, killing more than 100 people.
The group has been decimated in the past 18 months by a sustained military campaign. However, General Rodolfo Garcia, the army's vice chief of staff, believes its members may be seeking to regroup.
"The Abu Sayyaf have been marginalized, and largely their strength had been reduced," he said. "But there is always a danger that is ever-present when a group starts to get marginalized, they would always would want to try to come back, come back with a revenge."
General Garcia says the government is looking at the possibility that members of Jemaah Islamiyah, a regional terrorist group, provided funds to the Abu Sayyaf to help it rebuild. The two organizations are suspected of linking up to stage bomb attacks in Manila three years ago.