MANILA - An 84-year-old professor from Australia was barred from entering the Philippines by immigration authorities on Wednesday midnight for alleged joining a rally three years ago.

Professor Gill Boehringer has been held at the Ninoy Aquino International Airport since his arrival from Sydney, said Tinay Palabay of Karapatan, the group giving him paralegal support.

"He was told that he was on our blacklist for allegedly joining protests but he was not shown any documents whatsoever and was not given any chance to dispute the charges or allegations against him," she told ABS-CBN News Thursday.

She said Boehringer, who arrived in the Philippines to visit his Filipina wife, has been active in campaigning for human rights in the country since the time of then-President Gloria Arroyo.

On Thursday noon, Immigration spokesperson Dana Sandoval confirmed that Boehringer was blacklisted for reportedly participating in a rally in November 2015.

She said the professor's participation in the protest was “in clear violation of the BI Operations Order prohibiting foreigners in engaging in political activities in the Philippines.”

“Inclusion in the blacklist means that the subject is a threat to public order and safety, and blacklisting minimizes that risk,” she said, adding that the blacklist may be lifted if Boehringer's submits sufficient proof to reverse the order.

Meanwhile, Physician Geneve Rivera-Reyes recommended that a medical specialist see the professor first before being deported because he has a history of "an almost fatal pulmonary embolism."

Dr. Rivera-Reyes, who was requested by Boehringer to check on him at the airport, said the old man is also suffering from cellulitis on both legs.

"For humanitarian reasons, the BI should consider that it is not safe for Boehringer to be made to travel again without a medical specialist's clearance," the doctor said in a statement.

Karapatan condemned what it calls harassment against human rights defenders like Boehringer and Australian nun Sr. Patricia Fox, whom immigration authorities also want deported.

"We call on immigration authorities to respect the rights of Prof. Boehringer, including his right to due process and to have access to his family, lawyers and doctors, and his rights as a human rights defender," the group said in a statement.

The Immigration last July 19 ordered the deportation of Fox for her "involvement in partisan political activities." The nun was only doing missionary work for nearly three decades in the Philippines.

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