Law enforcement officers from Philadelphia and Bucks County, Pennsylvania, returned on Thursday to the 90-acre Solebury Township farm property where investigators discovered a common grave last week.

The Philadelphia Inquirer reports that numerous police officers and detectives performed a “walk-through” of the property on Thursday, a week after  Law enforcement officials told the newspaper that the search was done to ensure that police recovered all possible evidence before releasing the property.

“There is increased activity out on the Solebury property today because investigators are considering releasing the crime scene soon,” Bucks County District Attorney Matt Weintraub said in a statement.

“Because of that, and because renewed probable cause would be required for us to revisit the property once it is released to its owners, we want to make absolutely certain that we have not missed any evidence before departing.”

As CrimeOnline previously reported, during Cosmo DiNardo’s confession to the murder of four Bucks County young men, he is believed to have admitted to killing two additional people in Philadelphia when he was a teenager.

Philadelphia Police Commissioner Richard Ross said in a television interview earlier this week that his department had not had a chance to speak to the confessed murderer just yet, but hoped to.

“In order for us to lend any credence to (DiNardo’s claims) we have to talk to him directly, which we will do if we get that opportunity,” Ross said.