An Australian nun was arrested and briefly detained earlier this week in the Philippines as the government cracks down on foreign human rights activists in the country.

Sister Patricia Fox was arrested April 16 by immigration authorities at her convent, where she serves as the Philippine superior of the international Catholic congregation Sisters of Our Lady of Sion. She has been working primarily with the rural poor in the country for the past 27 years.

Fox was held for 22 hours by authorities before being released, after "no probable cause" was found for her arrest and she was proven to be a legally documented alien with a missionary visa, according to UCA News. There is still a pending further investigation of her activities to determine whether she should be deported.

The Catholic Bishops Conference of the Philippines' news outlet (CBCP News) reported that they were told Fox was arrested for being an "undesirable alien" for participating in regional farmer protests.

The Philippines' Intelligence services (NICA) have also charged Fox with participating in anti-government rallies. The organization claims it has a photo of the nun with a clenched fist holding a sign that says "Stop Killing Farmers", according to Newsweek.

Immigration law in the Philippines stipulates that participating in rallies and political activities is a violation of the right to stay in the country.

Jobert Pahilga, Fox's lawyer, denied these claims in a statement and said that she "has done nothing wrong or illegal that would warrant her arrest, detention and possible deportation."

He said that his client was traveling to Tagum City to gather data on human rights violations against farmers in the area.

Fox said that she has stood in solidarity with the rural poor during rallies, but not as a political action.

"I would call it religious because we are called to stand beside the poor," she told CBCP News. "I haven't joined partisan political rallies but I have been active in human rights issues."

Several human rights and Church leaders have denounced the arrest of the nun, including Manila Auxiliary Bishop Broderick Pabillo.

Pabillo told UCA news that Fox's arrest was a "form of persecution and harassment" and that the nun "is too old to run from the government or from whatever allegations they are accusing her of."

"This is political," Pabillo added. "The government is trying to intimidate individuals and groups who are in pursuit of social justice for the oppressed and the poor."

Fox is among several foreign human rights activists who have been arrested or barred from re-entering the Philippines in a recent crackdown on foreigners by Philippine President Rodrigo Duterte's administration.

"There's no martial law yet but they are already going after people who oppose them," Pabillo told CBCP News.

Fox will remain in the Philippines for the forthcoming investigation.

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