MANILA—A sister of human rights defender Dr. Maria Natividad Marian Castro on Monday belied allegations she is a ranking member of the central committee of the Communist Party of the Philippines–New People's Army.

"Hindi ako naniniwala na ang kapatid ko ay kasapi ng CPP-NPA. Hindi po siya kasapi. Ang kapatid ko ay doktor. Doktor po siya para sa mga mahihirap," Menchi Castro told ANC's "Rundown".

"Dito sa Butuan, nakatira siya dito. Naninilbihan para sa mga mahihirap na tao. Wala po sa kaniya 'yung pag-iisip na NPA."

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In a press release, the police said Castro was arrested in San Juan on Friday over charges of kidnapping and serious illegal detention.

The police identified Castro as a CPP central committee member and head of the CPP-NPA national health bureau in Barangay Libertad, Butuan City.

In the interview, Menchi said the arresting officers presented the arrest warrant but refused to identify themselves.

She was also manhandled by the officers during her sister's arrest, she said.

• Rights groups, lawyers ‘gravely concerned’ over Naty Castro’s whereabouts

Menchi said she was worried for her sister's safety and health.

"She has comorbidities. She's diabetic and then she's also hypertensive. So, we were not allowed to give her any medicine when she was picked up in Manila, in San Juan. So, it took a long time for us to find her and to be able to provide her with her medicine," she said.

Some of the detainees in the detention center in Bayugan, Agusan del Sur are also not fully vaccinated, she added.

Despite her sister's arrest, Menchi said their family is proud of what Castro has done as a doctor.

"Kami bilang pamilya, we are so proud of my sister. Kasi ang sister ko, si Dr. Naty, mahal niya ang Pilipinas, mahal niya ang mga Pilipino. Inalay niya ang sarili bilang doktor para pagsilbihan ang mga mahihirap na tao. Wala po silang access sa health-care," she said.

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