A dispatcher took eight minutes to send a police car to Josh Powell’s home after a social worker dialed 911 Sunday to report that he had locked himself and his sons inside his home and she smelled gasoline, and it was 22 minutes before police actually arrived, according to CNN.

Now authorities are planning an investigation of the response to the call. CNN reported that Pierce County Sheriff’s Department spokesman Ed Troyer criticized the dispatcher’s “etiquette” in handling the social worker’s call about what she said warned him a life-threatening situation.

The social worker’s husband told CNN affiliate KCPQ that she was “very upset and traumatized” after witnessing the house explode with Powell and the two boys inside. Speaking to HLN’s Nancy Grace Wednesday, the boys’ grandparents—the parents of missing mother Susan Cox-Powell—said they do not blame her for what happened.

Josh Powell’s sister said in an interview airing Thursday that Josh had been the victim of harassment, abuse and lies since his wife disappeared in December 2009 and she still believes he is innocent in that case.

Alina Powell told ABC News that she was initially suspicious of her brother’s possible involvement in what happened to Susan, but she felt she never heard anything “remotely suspicious” about him in the months afterward. She said he was damaged by the “lack of due process” and public criticism he faced.

“He must have just felt that there was only one way left for him to protect his sons from the pain,” Powell said, claiming that police have interfered with his custody case involving the children. Powell lost custody of the boys last fall. Authorities say he killed them during what was supposed to be a court-ordered supervised visitation.

West Valley City Police have received new tips about Susan Cox-Powell’s disappearance since Sunday’s events, the Salt Lake Tribune reported. Chief Buzz Nielsen told the paper that officers are reviewing the tips to determine if any are credible.

Nielsen said police eventually want to talk to Josh’s father, Steven Powell, but they do not want to interfere with his prosecution in Washington for charges unrelated to the case.

For the latest crime and justice news, watch "Nancy Grace" weeknights at 8 p.m. and 10 p.m. EST on HLN.

Samantha Koenig, 18, was last seen on February 1 working at a Common Grounds coffee shack in Anchorage. Police told the Anchorage Daily News that surveillance video showed a man in a hooded sweatshirt forcing Koenig out of the coffee stand and out of the frame. They believe the abductor was carrying a weapon.

Lt. Dave Parker of the Anchorage Police Department told HLN that investigators will not release the video because it is impossible to make out the face of the suspect in it, so they believe it would not assist in finding Koenig. Parker also declined to say what items, if any, Samantha left behind at the coffee hut.

Samantha’s father, James Koenig, told HLN her boyfriend was supposed to pick her up from work that night, but there was another man who she recently had been having problems with. He would not discuss the nature of her relationship to that man, but court records show the teen filed a petition for a protective order against a 24-year-old man last November accusing him of sexual assault. The petition was dismissed when she did not appear for a hearing.

Police told the Anchorage Daily News that the man is not considered a potential suspect in Koenig’s disappearance. The paper reported Wednesday that the FBI has now joined the investigation.

For the latest crime and justice news, watch Nancy Grace weeknights at 8 p.m. and 10 p.m. EST on HLN.