BOSTON (CBS) – Prosecutors filed new charges Tuesday in the tragic death of an 11-year old Haverhill girl who was exposed to fentanyl. Investigators now say the child was sexually assaulted the night she was found unresponsive in her great uncle’s apartment in Lawrence.

Miguel Rivera, 58, of Lawrence was arrested earlier this month and charged with the death of his great niece. The girl was staying at Rivera’s apartment on December 15 when she began struggling to breathe in the middle of the night.

READ MORE: NH Police Searching For Missing 5-Year-Old Boy Elijah Lewis

Miguel Rivera is brought into court on January 29, 2019. (WBZ-TV)

She was rushed to the hospital and died several days later. Last week, toxicology reports indicated she was exposed to the deadly opioid fentanyl.

Relatives cried loudly as Rivera walked into court Tuesday. Prosecutors announced he is now charged with rape of a child with force.

READ MORE: Case Of Rat-Borne Bacterial Disease Identified In Boston

According to court documents, Rivera did not initially tell investigators he flushed sleeping pills down the toilet the night the girl became ill. Rivera also is accused of waiting 13 minutes to call 911 while the girl struggled to breathe.

The documents allege that the girl’s brother told police that Rivera gave the siblings “a little red pill” before they went to bed on December 15.

Initially, Rivera was charged with lying to police and permitting substantial bodily injury to a child.

MORE NEWS: 12-Year-Old Boy Struck By Car, Seriously Injured In Taunton

On Tuesday a judge ordered him held without bail. He is due back in court March 13.