A 71-year-old Australian nun was arrested in the Philippines on Tuesday for “engaging in political activities,” another indication that Rodrigo Duterte’s administration is cracking down on political dissidents.

Sister Patricia Cox was reportedly detained for “attending protest rallies and engaging in political activities” against Duterte’s presidency. She was later released, but investigations into the incident will continue.

Her lawyer, Jobert Ilarde Pahilga, maintained that Cox had “done nothing wrong that would warrant her arrest, detention, and possible deportation,” adding that National Intelligence Coordinating Agency complained she was an “undesirable alien” because of her involvement in anti-government activities.

“She is a human rights and a genuine agrarian reform advocate who tirelessly provided various social service to farmers including the farmers of Hacienda Luisita,” Pahilga said in a statement.

The arrest immediately drew criticism from government opposition, who expressed fear that the government is cracking down on opposition activists while describing Cox as a tireless human rights campaigner.

“The emerging trend on the crackdown against foreign activists in the country is alarming as exhibited by the harassment and casual arrests of the two human rights advocates, who were not even in protest activities or rallies when taken into custody,” the opposition Liberal Party said in a statement.