The President’s stern warning came a day after a bomb exploded in a public market in Koronadal of southern Philippines, killing three and injuring twenty nine others.
The authorities suspect rebels of the Moro Islamic Liberation Front (MILF) of being behind the attack.
Visiting the blast site, Arroyo insisted that even the planned peace talks with the separatist rebels would not deter her from taking strong action against them if they were found responsible.
“Nothing in the peace process will deter us from punishing terrorists and bringing them to justice,” Arroyo said.
“This even will not deter us from preparations for the peace negotiations unless MILF is proven to be involved,” she added.
Regional police chief Manuel Raval said the latest blast had “the same pattern, the same operation, the same targets” as the previous bomb attacks blamed on the MILF.
Interior Secretary Jose Lina claimed the suspects were hiding in MILF ‘sanctuaries” but did not say if they were linked to the rebels.
A spokesman of the MILF however denied any involvement and demanded that Malaysia, which has been invited to monitor any ceasefire between MILF and Manila, should send a team to investigate the incident.
“We want the matter to be thoroughly investigated. We requested the Malaysian monitoring team to be dispatched immediately and this will become their test mission,” MILF spokesman Eid Kabalu said.
Both the government and the MILF have been working to reopen peace talks with Malaysian mediation to end fighting in southern Philippines.
The 12,500-strong MILF nurtures separatist ambitions and has been battling government forces for years.