(UPDATED) - Immigration authorities have arrested a 71-year-old Australian nun known to be a human rights advocate for "attending protest rallies and engaging in political activities".

Sister Patricia Fox, superior of the Our Lady of Sion congregation in the Philippines, was taken into custody by immigration agents at their mission house in Quezon City at around 2 p.m. Monday, April 16, the Catholic Bishops Conference of the Philippines (CBCP) said in a statement.

Fox is being detained at the Bureau of Immigration (BI) intelligence division in Intramuros, Manila, a BI statement confirmed Tuesday, April 17.

The agency said Fox was arrested for violating the conditions of her stay "by attending protest rallies and engaging in political activities." Her arrest was based on a mission order issued by Commissioner Jaime Morente.

The BI said Fox has already appeared before a Special Inquest Prosecutor and was required to submit her passport for further verification.

Following the procedure, the prosecutor will recommend whether to file charges against the nun or release her for further investigation.

Kalookan Bishop Emeritus Deogracias Iñiguez visited her Tuesday morning, April 17, while activists staged a protest rally outside the BI office, the CBCP said in a series of tweets.

The CBCP statement said the nun has “worked in the Philippines for 27 years helping farmers and indigenous peoples.”

“She recently joined an international fact-finding and solidarity mission that investigated alleged rights abuses against farmers and Lumad in Mindanao,” the group added.

Her arrest came on the heels of the deportation of an official of Party of European Socialists (PES), who had traveled to Cebu to attend the Akbayan Party-list Congress.

Giacomo Filibeck was handed a blacklist order upon arrival at the Mactan Cebu International Airport Sunday, April 15, and refused entry. He was shortly deported.

Read: EU party official denied entry in Cebu; Palace defends move

Justice Secretary Menardo Guevarra, in a separate statement, said the case of Fox has nothing to do with her being a nun or with the latter's advocacies. He said like other foreigners, Fox has to abide by the immigration laws.

According to the CBCP, Fox’s legal counsel Jobert Pahilga said his client faces deportation.

Pahilga said the BI will keep Fox’s passport pending an investigation. (MVI and KAC/SunStar Philippines)