Man charged in Iowa fire that killed alleged sex abuse victim, her cousin

Shakiah Cockerham, left, and Melanie "Paige" Exline

CBS affiliate KCCI

GUTHRIE CENTER, Iowa -- Law enforcement officials have charged an Ames man in a May house fire at Guthrie Center that killed two young girls.

The Guthrie County Sheriff's Office said in a news conference Wednesday that 26-year-old Patrick Ryan Thompson is charged with two counts of first-degree murder, two counts of attempted murder and one count of arson. It was not clear whether he has an attorney.

Investigators had already determined that arson caused the May 15 fire that killed cousins 16-year-old Shakiah Cockerham and 12-year-old Melanie "Paige" Exline and injured their uncle, 54-year-old William Long III, and grandmother, 74-year-old Shirley Exline.

CBS affiliate KCCI reports that investigators believe Melanie was sexually abused by two of her relatives, James and Noah Exline. The two men, who are Thompson's stepfather and stepbrother respectively, are each facing multiple sexual abuse charges.

Melanie was considered the sole witness in the case against Noah Exline. Greene County prosecutor Nick Martino told KCCI that the girl's death does not mean Noah Exline's upcoming trial will be abandoned, but it does make prosecuting the case "more difficult."