Philippine troops and police searched Monday for a 78-year-old Irish missionary after heavily armed men abducted him from the garden of his residence in the country's volatile south. The six gunmen dragged the Rev. Michael Sinnott into a van in front of his horrified aides inside the Columban House compound in Pagadian city, Zamboanga del Sur province, late Sunday, regional police commander Angelo Sunglao said. 'They could not do anything because the abductors had powerful weapons,' Sunglao told The Associated Press. No group has claimed responsibility for the kidnapping, but suspicion fell on Muslim guerrillas who have been fighting for a separate homeland in the predominantly Roman Catholic nation's south for decades and have in the past kidnapped foreigners, including priests. The abductors took Sinnott away by sea on a motorboat toward a town called Tukuran, Sunglao said, citing fishermen who saw the abduction. The van was later found abandoned and burned near the Catholic mission house. Police and troops were mobilized to search the area, said military spokesman Maj. Ramon David Hontiveros. Al-Qaida-linked Abu Sayyaf militants and insurgents from the larger Moro Islamic Liberation Front have a presence in the vast Zamboanga peninsula, but Sunglao said it was too early to pinpoint any group. Sinnott's group, the Missionary Society of St. Columban, confirmed his abduction, saying he was taking an evening stroll in the convent's garden when he was taken by the gunmen. The group appealed for prayers for his safe recovery. The Columban regional director, Patrick O'Donoghue, said he was worried because Sinnott has a heart condition and was not carrying his medication when he was taken. Sinnott has worked in the Philippines for decades. The group said he was first assigned in the southern Philippines between 1957-66, then returned in 1976. He has been involved in a school for handicapped children since 1998. Several priests have been kidnapped in recent years in the region. Mostly recently, an Italian priest, Giancarlo Bossi, was kidnapped allegedly by members of the Moro Islamic Liberation Front and the Abu Sayyaf in nearby Zamboanga Sibugay province in June 2007. He was freed after 39 days. The rebel front denied any involvement. The government then denied speculation that a ransom was paid to win Bossi's release. The 11,000-strong Moro Islamic Liberation Front, which has been engaged in on-and-off peace talks with the government, has denied any involvement in kidnappings for ransom or any alliance with the smaller and more violent Abu Sayyaf. The Abu Sayyaf is believed to have about 400 fighters. U.S. and Philippine security officials say it has received funds from al-Qaida and is suspected of sheltering militants from the larger Southeast Asian terrorist group Jemaah Islamiyah. 