Abducted Columban missionary Fr Michael Sinnott is believed to have access to the medication he urgently needs to take for his heart condition, as efforts to secure his release intensify.

A public rally was held in the Philippines yesterday to demand the release of the 79-year-old who was kidnapped there three weeks ago. Fr Pat Raleigh, vice director of the Columban order in Ireland, said concerns remained for the priest's health but it is believed that his kidnappers have allowed him to keep taking his vital medication. "He had a heart by-pass four years ago. Our main concern is his medication. But it seems, I've been credibly assured, he has been given his medication," he told the Sunday Tribune.

Fr Raleigh hit out at media reports that claimed the priest had died. "There was a rumour that he died which was unfortunately printed in one of the newspapers [the Daily Star] here. We are concerned for his welfare but we are confident he is alive."

Fr Sinnott was kidnapped by six armed gunmen at his Missionary Society of Saint Columban compound in the southern city of Pagadian, on Mindanao island.

Fr Raleigh said it was not policy for the Columban fathers to pay any ransom if demanded. "He was taken from the compound and put into a mini-van. He was then taken by speedboat to where, we do not know. The $64,000 question is: why? Why would people kidnap an elderly man? It could be for money but I'm not aware of any ransom being demanded," he said.

Philippine authorities have announced a reward of 200,000 pesos (€2,832), as concern for the missing missionary grows. "He was my rector. He is a man of deep spirituality, a man of prayer," said Fr Raleigh. "He is a very solid, quietly spoken man who is very determined. He is full of integrity. There is a tremendous amount of respect for him in the Philippines. He works with children with disabilities. These children would have otherwise been ignored."

Fr Raleigh praised the efforts of the Department of Foreign Affairs and local bishop Emmanuel Cabajar for their ongoing efforts to secure his release.

Alan Molde, spokesman for the task force handling the abduction, said there had been no contact with the kidnappers and that police were following up all leads, including anonymous mobile-phone messages.

The Moro Islamic Liberation Front, a Muslim separatist group, has denied any part in the kidnapping and said it was prepared to help in the rescue search.

Now there are suspicions the Abu Sayyaf, a militant Muslim group blamed for the nation's worst terrorist attacks, may be behind the abduction.