(CNN) -- An American Catholic priest has been arrested in the Philippines -- and charged in US federal court -- on suspicion of sexually abusing boys in the Southeast Asian country where he's lived for decades, authorities in both nations announced.

The Rev. Kenneth Bernard Pius Hendricks, 77, originally from Cincinnati, was arrested Wednesday in the Philippine city of Naval after several alleged victims came forward to Philippine and US investigators last month, authorities said.

Though court documents filed in late November cite five accusers, a total of 10 accusers have now come forward in the Philippines, alleging Hendricks sexually abused them when they were boys, US Homeland Security Investigations Special Agent Steve Francis said Thursday in Cincinnati.

But because Hendricks also spent parts of the year in the United States, investigators are asking the public in both countries for information about the priest.

"It's horrifying ... abusive conduct," US attorney Benjamin Glassman said Thursday about the allegations in the Philippines. "It's grooming children -- young children -- that are interested in being involved in church activities and taking those kids and sexually abusing them."

"He befriended them, he would invite them to his residence" before engaging in progressively intimate contact, sometimes including oral and anal sex, Glassman said.

Hendricks is charged in federal court in Cincinnati on a count of engaging in illicit sexual conduct in foreign places, punishable by fines and/or up to 30 years in prison.

Hendricks was being held in a Philippines Bureau of Immigrations holding facility in Manila, the bureau said. His attorney in the Philippines, Mario Opeña, told CNN that the priest maintains the allegations are false.

"As far as Father Hendricks is concerned, the allegations are not true and he will prove his innocence in court," Opeña said.

'Other children may have been impacted'

Hendricks has been a priest in Naval, a city of about 50,000 people in central Philippines, the country's Bureau of Immigration said.

Of the allegations cited by the five accusers in the affidavit, the earliest dates to 2009. The accusers' ages at the start of the alleged abuse range from 7 to the teens, Glassman said.

"We believe there is a high probability that other children may have been impacted by his alleged actions," Francis said.

Hendricks was ordained as a priest in the Philippines after arriving in the country in the 1960s, said the Rev. Benjamin Pantas, spokesman for the Diocese of Naval.

The Naval diocese is conducting a parallel, independent investigation, Pantas said.