Robert Seman Jr, who is accused of repeatedly raping a 10-year-old girl and then killing her and her grandparents in a house fire, has jumped to his death from a courthouse balcony before standing trial

The disturbing moment a man accused of repeatedly raping a 10-year-old girl and later killing her and her grandparents in a house fire jumped to his death from a courthouse balcony has been captured on camera.

Robert Seman Jr, 48, was set for trial this week at the Mahoning County Courthouse in Youngstown, Ohio, over the deadly arson when he threw himself from the fourth-floor.

Seman faced the death penalty if convicted of aggravated murder charges in the March 2015 deaths of 10-year-old Corrine Gump, 63-year-old William Schmidt and 61-year-old Judith Schmidt.

A Youngstown Vindicator reporter who witnessed the incident said the 48-year-old's body was covered by a white sheet inside a marble rotunda, but his arms were visible as they were sticking out.

In the short clip, Seman is first seen walking out of the courtroom with two officers. He then slows down, allowing the officer who was behind him to draw level with him.

He then took three steps to his right, before throwing himself over the low railing.

The two police officers are seen rushing to the railing desperately, before they make their way downstairs. People are seen emerging from the courtroom at the same time.

According to Mahoning County Sheriff Jerry Greene, Seman was not restrained by the deputies escorting him through the building, “Due to the fact that the courts do not want individuals on trial to be seen with restraining devices on, or per se, in custody,” Greene told WKBN.

Seman had swapped his orange jail jumpsuit for civilian clothing before going to court and wore a brace under his pant leg to prevent him from running.

Assistant Prosecutor Dawn Cantalamessa, who was leading the case against Seman, told the newspaper it was 'telling' that the accused opted to leap to his death instead of facing trial.

The shocking video starts by showing Seman walking with two police officers, before just seconds later he hurls himself over the balcony

The shocking incident was recorded on surveillance cameras inside the courthouse, and broadcast by WKBN.

Prosecutors had claimed Seman torched the Schmidt's family home shortly before he was set for trial on the rape charges.

Police discovered burns on Seman's body after his arrest over the gasoline-fueled arson.

Seman had unwaveringly claimed he was innocent of both the murders and the rape accusation.

The 48-year-old's body was later seen on the floor of the courthouse with a white sheet over it. His arms were sticking out

Seman allegedly repeatedly raped 10-year-old Corrine Gump (left) and then torched the home she was in with her grandparents before he was due to face those charges. Seman was dating Corrine's mother, Lynn Schmidt (right)

Seman Jr, 48, was set for trial this week at the Mahoning County Courthouse (pictured) in Youngstown, Ohio, over the deadly arson when he threw himself from the fourth-floor

Robert Seman Jr, repeatedly raped a ten-year-old girl and then killed her and her grandparents by torching their home

The alleged rapes took place over a number of years while Seman was dating Corrine's mother, Lynn Schmidt.

It emerged in March 2015, following the emergence of rape allegations against Seman, Schmidt and her daughter moved in with her parents, but she eventually headed back to her boyfriend's home.

Investigators who searched the home after the fire found all three bodies on the second floor.

They were out of their beds and the way they were positioned suggested they were trying to get out, Fire Chief John O'Neill told the Vindicator at the time.