A person under Benito Marquez's name wrote on Facebook: "If you hear anything about him or where [he's] at notify Bj Eastman [Ben's dad]"

Teen Murder Suspect Seemingly Posted About His Missing Friend on Facebook Before Body Was Found

Last week, 16-year-old Benito “Benny” Marquez apparently took to Facebook to ask for prayers for his missing friend Benjamin Eastman III, who lived near him in Randle, Washington, and hadn’t been seen since June 23.

“Please,” a person under Marquez’s name wrote late on June 27, “if you hear anything about him or where [he’s] at notify [Eastman’s dad] and send prayers out for his family.”

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(PEOPLE has reviewed the post but could not confirm it was written by Marquez; however, the Facebook account matches his name, photo and basic biographical details.)

Along with the post, the account shared the missing-persons poster for Ben, also 16.

Within a day, Eastman was found dead in a “shallow grave” on property in Randle owned by Marquez’s relative, according to the Lewis County Sheriff’s Office. Marquez and his older brother, Jonathon Adamson, were soon accused of murdering Eastman in a vicious assault in the woods.

Adamson, 21, and Marquez are both charged with first-degree rape and murder as well as tampering with physical evidence and unlawful disposal of remains in Eastman’s beating death.

Image zoom Benjamin Eastman III Ben Eastman/Facebook

Image zoom Ben Eastman Ben Eastman/Facebook

According to charging documents obtained by PEOPLE, Marquez, who is being prosecuted as an adult, was a longtime friend of Eastman’s. He and Adamson allegedly “lured” Eastman into the woods for a camping trip last week, but then knocked him to the ground and assaulted him for approximately “20 to 45 minutes,” kicking him over and over and over again.

The charging documents allege that Adamson told investigators he and Marquez sexually assaulted Eastman with a stick while Ben was still alive.

Before burying Eastman, the brothers beat him in the head with a rock to ensure he was dead, authorities suspect.

A motive in the attack is unclear.

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Marquez was an early part of the investigation, according to the sheriff’s office. Before they found Eastman’s body on June 28, deputies learned that he “had planned on meeting up” with Marquez not long after he was last seen alive. In an interview with investigators, however, Marquez allegedly said Eastman never came over and that he hadn’t seen the other teen in several days.

Jail records show Adamson was booked in Eastman’s death on Saturday, two days after Eastman’s body was found. Marquez was booked on Monday.

They appeared in court on Monday and remain in custody in lieu of $10 million bond.

Neither Adamson nor Marquez has pleaded to their charges. Information about whether they retained attorneys who could comment on their behalf was not immediately available on Thursday.

They are reportedly set to return to court on July 12.

Ben’s father, Benjamin “B.J.” Eastman Jr., sat in the front row at Monday’s court hearing in order to face the suspects, he told local TV station KOMO.

“I wanted them to look at me,” B.J. told the outlet. “I wanted to look them in the eye.”

Of the accusations, he said, “When I heard they were charging them with rape and that process, that really blew me hard.”

Still, he said, “It’s easy to get caught up in the negative aspect of this, but I remember my son and his smile.”