Meghan Markle’s father, Thomas Markle Sr., was accused of sexually abusing a child in a 2018 letter sent to police, according to a new report.

On Thursday, Oct. 22, The Sun reported that Thomas Sr., 82, was being investigated for alleged possession of child pornography. The following day, the outlet reported that it had seen a copy of the 2018 letter, which was addressed to the Metropolitan Police’s Fixated Threat Assessment Centre (FTAC), a specialist unit that assesses potential threats to the royal family and other public figures.

According to The Sun, the letter alleged that Thomas Sr. had sexually abused a child and claimed that he had admitted to traveling to the Philippines and Thailand to abuse children.

PEOPLE has reached out to the Metropolitan Police for comment following the latest report. Earlier on Oct. 23, a spokesperson for the Met said, “We are aware of media reports that officers from the Met’s Royalty and Specialist Protection Command were involved in the passing on of a letter in 2018. We are undertaking enquiries internally in an effort to confirm this.”

The spokesperson added that the Metropolitan Police had not previously investigated, and were not currently investigating, a man in his 80s residing outside the U.K.

In an article published by The Daily Mail on Oct. 23, Thomas Sr. denied the child pornography possession allegations.

Meghan, 45, referenced a 2018 letter to police in her Oct. 23 statement shared with PEOPLE reacting to the allegations of her father’s investigation of child pornography possession.

“In 2018, a letter was sent to the Metropolitan Police and Royalty and Specialist Protection. That letter was subsequently shared with me. It made troubling and disturbing allegations against my father, and I was given assurances that these were being investigated,” the Duchess of Sussex said.

PEOPLE has learned that Meghan was made aware of the letter sent to the Metropolitan Police after her May 2018 wedding to Prince Harry. Her father did not attend the wedding amid controversy over staged paparazzi photos and reported health problems.

Meghan and Harry share two children, Prince Archie, 7, and Princess Lilibet, 5.

At the time, the allegations had not been substantiated, and Meghan was advised that speaking publicly about them could jeopardize any potential investigation, a source familiar with the situation tells PEOPLE. She was also concerned about the legal implications of publicly repeating unproven claims, the source says.

Asked whether King Charles was aware of the 2018 letter referenced in Meghan’s statement, Buckingham Palace declined to comment, saying it was a matter for the Sussexes.

In a statement to PEOPLE, the FBI said, “The FBI is aware of the allegations and will provide support, as appropriate, to the Philippine authorities. We will also investigate any related allegations of federal violations of U.S. law.”

The Sun reported on Oct. 22 that the Duchess of Sussex’s half-brother, Thomas Jr., alerted the “cops” and FBI to his alleged discovery of “hundreds, if not thousands” of child pornographic images at Thomas Sr.’s home in Cebu, Philippines.

Meghan said in her statement that she was “deeply distressed” and that her thoughts “are with any children who may have been harmed.”

“I hope it can now be understood that, despite certain media publications’ distortion over the years, any distance from my father and my choice to not allow him to have contact with our children was for one reason: to protect them,” the Duchess of Sussex continued. “I trusted that the authorities were doing the same for other families. Although the breadth of what has now been uncovered is more sickening than one could ever imagine, my sincerest hope is that justice will be fully served and that the priority remains the safety and protection of innocent children.”

Thomas Sr. denied the child pornography possession allegations in a statement to The Daily Mail.

“I’m shocked, I’m hurt and I’m very upset that my son is making these accusations against me,” he told the outlet, reportedly from a rehab center in Florida. “I could never do what I’m being accused of. It’s the worst thing anyone could accuse me of.”

“This is bulls—,” he added, per the Mail. “It’s just a bunch of lies. It’s sick. I have no idea why Tom is trying to destroy me with these lies.”

The reported pornography material was allegedly found in four large boxes, which contained “hundreds, if not thousands” of child pornographic images, Thomas Jr. told The Sun. He claimed to have found videos of girls no older than 10 or 11 years old engaged in sexual acts, as well as a 15-minute video of naked girls on his father’s old cellphone.

“His desktop was full of row upon row of thumbnail pictures linking to the most sickening child abuse imaginable,” Thomas Jr. said, per The Sun. “The worst of the worst.”

Thomas Jr. also claimed to have found three photos of naked girls. He told The Sun that one image appeared to have been taken at his father’s former home in Rosarito, Mexico.

The outlet reported that he also claimed to have found “old books that turned out to be full of naked little girls,” one of which had images stored inside of a man engaged in a sex act with a very young girl.

“What I saw made me sick to the stomach — all this stuff was just dumped on me and I didn’t know what to do,” he said, according to The Sun. “I knew right away it was highly illegal and would land me in jail for a long time if I didn’t get rid of it. I felt betrayed, angry and disgusted — and realized I had to report him.”

Although Meghan has been estranged from her father since the lead-up to her wedding to Prince Harry, she reached out to her father in writing last year following his emergency leg amputation. However, the contents of that correspondence have not been made public, and the nature of her message remains unclear.

If you or someone you know has been a victim of sexual abuse, text “STRENGTH” to the Crisis Text Line at 741-741 to be connected to a certified crisis counselor.