Story highlights Jerry Andrew Active, 24, is being held on $1.5 million bond

He is charged with murder, sexual assault and burglary

Active was arrested about a block from where the alleged attack took place

A man is accused of breaking into an Anchorage, Alaska, home over the weekend, sexually assaulting an elderly woman, killing her and her husband, and sexually assaulting the couple's 2-year-old great-granddaughter before fleeing the scene in his boxer shorts.

Jerry Andrew Active, 24, was arrested about a block from the home. He was charged with first and second degree murder, sexual assault and burglary, said Anchorage Police Sgt. Slawomir Markiewicz. Active is being held on $1.5 million bond.

Markiewicz said police were called to the home shortly before 8 p.m. Saturday. When they arrived, they found Touch Chea, 71, and his wife, Sorn Sreap, 73, dead, apparently due to blunt force trauma to the head and face, Markiewicz said. Autopsies are pending.

Police also found in the home the couple's great-granddaughter, who was sexually assaulted. Sreap had also been sexually assaulted, police said.

"I've been in the homicide unit for the last eight years and it's certainly one of the worst homicides we've seen in our town, in our city," Markiewicz told CNN's Brooke Baldwin Monday night.

The sergeant said the 2-year-old's father told police that he and his wife, who is pregnant, lived in the home with their children -- ages 4 and 2 -- along with Chea, Sreap and another relative.

They took their 4-year-old to the movies on Saturday, leaving their youngest in the care of the child's great-grandparents.

When they returned, the front door was locked and there was a chain on from the inside, blocking their way.

The father was able to open the door a few inches and saw the bodies of Chea and Sreap on the floor.

He broke a window, ran inside, yelled for someone to call 911, and found the suspect naked with his 2-year-old, according to Markiewicz.

A fight ensued, but police said Active pulled on his boxer shorts and escaped, albeit briefly.

A 91-year-old relative, suffering from dementia, was also at home at the time of the attack. She was uninjured.

The 2-year-old was taken to a medical facility that specializes in the treatment of sexual abuse. She underwent surgery for her injuries, Markiewicz said.

Police believe the attack was random and that Active did not know the victims.

Active had previously been convicted of sexual assault that involved an 11-year-old child, Markiewicz said.

It was not immediately clear whether Active had retained an attorney.