WORCESTER — A somewhat emotionless Alberto L. Sierra pleaded not guilty in Worcester Superior Court on Thursday to all counts against him in connection with the disappearance of his girlfriend’s 5-year-old son, Jeremiah Oliver of Fitchburg.
Handcuffed and wearing a dark-brown T-shirt, Sierra entered his pleas in a barely audible voice on new charges, including kidnapping, assault, and reckless endangerment.
His bail was set at $250,000 cash or a $2.5 million surety. He had little reaction when he was read the bail revocation warning, and after nodding that he understood, he looked around the courtroom while he was escorted out.
Several people in the courtroom who said they were there in support of Sierra would not comment.
The boy’s mother, Elsa Oliver, will be arraigned on Friday in Worcester Superior Court.
Jeremiah, who was last seen by relatives on Sept. 14 and whose disappearance is being handled as a homicide investigation, is listed as the victim for some of the charges, including those alleging kidnapping of a child and permitting an assault and battery on a child causing bodily injury. Two of his siblings are listed as victims on other charges.
A Worcester County grand jury indicted the pair last week.
Oliver is charged with assault and battery with a dangerous weapon, and three counts each of assault and battery and reckless endangerment of a child, kidnapping of a child, and permitting an assault and battery on a child causing bodily injury.
Sierra was arraigned on charges of kidnapping of a child, four counts of assault and battery with a dangerous weapon, two counts of assault and battery, three counts of reckless endangerment of a child, and single counts of indecent assault and battery on a child and assault and battery on a child causing bodily injury.
Most of the charges against Sierra list either Jeremiah or one of his siblings as the alleged victim.
Elsa Oliver is listed as the victim in one of the assault and battery charges and one of the assault and battery with a dangerous weapon charges. The victim of the indecent assault and battery on a child is not named in the charges.
Oliver, 28, and Sierra, 23, both of Fitchburg, were previously charged in Fitchburg District Court. Oliver was charged with two counts each of reckless endangerment of a child and being an accessory, after the fact, to assault and battery with a dangerous weapon in the district court.
Sierra was charged with two counts of assault and battery with a dangerous weapon and two counts of assault and battery on a child causing bodily injury.
Oliver is being held in lieu of $100,000 cash bail. Sierra remains in custody.