CHICAGO (CBS) — Opening statements began Friday in the Delphi, Indiana, murder trial of Richard Allen who is accused of the 2017 killings of Abigail Williams, 13, and Liberty German, 14.

Twelve jurors and four alternates were chosen Monday and Tuesday in Fort Wayne, Indiana, to hear the case.

Allen, 52, is charged with two counts of murder and two counts of murder while committing or attempting to commit kidnapping in the killings of the Delphi, Indiana, eighth graders, known as Abby and Libby. If convicted, Allen could face up to 130 years in prison.

Prosecutors opened the trial on Friday by describing the gruesome crime scene where the girls were found with their throats slit.

Jurors spent the morning hearing opening statements from both the prosecution and the defense.

The jury is made up of eight women and four men, plus four alternates, all selected from Allen County, two hours east of Delphi, in hopes a group of jurors from another county would have less knowledge of the case ahead of time.

The prosecution opened their case by taking the jury back to the day Abby and Libby were killed along a hiking trail in Delphi. Attorneys painted a picture of the gruesome way the teen girls were found, the video evidence found on Libby's phone, and the women who saw a man leaving the wooded area after the murders.

Prosecutors are trying to prove Allen killed the girls and hid in plain sight in the town for five years afterward. Other evidence they plan to show the jury over the coming weeks will include photos of the scene, video from Libby's phone, an unspent shell casing found next to their bodies, and Allen's alleged confession.

Allen's attorneys maintained he is an innocent man, telling the jury their focus is on the investigation itself, calling it "messed up from the beginning." They will try to prove the evidence does not support the prosecution's timeline, and claim Allen was never on the same trail as Abby or Libby on the day of the murders.

His team claimed evidence was lost and that Allen was never on the trail at the same time as the girls and pointed to inconsistencies in the state's timeline of events.

Jurors to be sequestered for trial

The jurors were sworn in Thursday for the trial in Delphi, a community of about 3,000 some 60 miles northwest of Indianapolis.

The trial is expected to last a month. The jurors will be sequestered throughout the proceedings, monitored by bailiffs and banned from using cellphones or watching news broadcasts.

Prosecutors said they plan to call about 50 witnesses, while Allen's defense attorneys expect to call about 120 people to the stand.

Allen, a pharmacy technician who had lived and worked in Delphi, was arrested in October 2022.

Delphi murders case

A relative had dropped the teens off at a hiking trail just outside Delphi on Feb. 13, 2017, but the two friends failed to show up at the agreed pickup site later that day. They were reported missing that evening and their bodies were found the next day in a rugged, wooded area near the trail.

Within days, police released files found on Libby's cellphone — two grainy photos and audio of a man saying "down the hill" — that they believed captured the killer.

On Feb. 14, the prosecution said the girls were discovered covered in blood with their throats cut. They said Libby was undressed. Abby had Libby's sweatshirt on and no jeans. The rest of their clothes were found in a creek, prosecutors said.

Investigators released one sketch of the suspect in July 2017 and another in April 2019. They also released a brief video showing the suspect walking on an abandoned railroad bridge.

After years of failing to identify a suspect, investigators said they went back and reviewed "prior tips."

Allen had been interviewed in 2017. He told the officer that he had been walking on the trail the day the girls went missing and that he saw three "females" at another bridge but did not speak to them. He said he did not notice anyone else because he was distracted by a stock ticker on his phone, according to an arrest affidavit.

Police interviewed Allen again on Oct. 13, 2022, when he reasserted he had seen three "juvenile girls" during his walk in 2017. Investigators searched Allen's home and seized a .40-caliber pistol. Prosecutors said testing determined an unspent bullet found between the teen's bodies "had been cycled through" Allen's gun.

According to the affidavit, Allen said he'd never been where the bullet was found and "had no explanation as to why a round cycled through his firearm would be at that location."