A Texas teen said he was sleepwalking when he stabbed and killed his twin sister

• A Texas teen said he was sleepwalking when he fatally stabbed his twin sister.
• Police arrested Benjamin Elliott, 17, on September 29 and charged him with murder.
• Elliott's lawyer said he does not have a history of sleep disorders and was not under the influence.

A Texas teen accused of killing his twin sister claimed in court that he was sleepwalking and was unaware of his actions, according to the local ABC News affiliate KTRK.

Police arrested Benjamin Elliott, 17, on Wednesday on suspicion of stabbing his sister in the neck. His attorneys told prosecutors Thursday morning that he woke up around 3 a.m. the morning of the incident in his sister Meghan's bedroom with a knife in her neck along with several stab wounds.

"The defendant stated after realizing he was not dreaming, he removed the knife and placed it next to the complainant, turned on the light to the bedroom, applied pressure to the wound with a pillow," a prosecutor said at Thursday morning's hearing.

Harris County Sheriff Ed Gonzalez told KTRK Elliott was the first person to call 911 emergency services, who instructed him to perform CPR on his sister. Authorities discovered Elliott still performing CPR on his sister when they arrived, but his attempts were unsuccessful: police pronounced Meghan Elliott dead at the scene.

Despite his sleepwalking claim, Elliott's attorney told prosecutors on Thursday morning he does not have any history of any sleep disorders and was not under the influence of alcohol or drugs during the stabbing.

Elliott's neighbor, Robert Dawson, said Benjamin and Meghan Elliott appeared to get along well.

"They get on a bus up here at the end of the street, and every day when they come home, they walk," Dawson told KTRK. "I mean, they don't walk hand-in-hand, but they give you the impression that they've very protective."

Authorities set Elliott's bond at $100,000. Inmate records show that the bond has not been paid as Elliott remains in a Houston jail.

The Harris County Sheriff's Department did not immediately respond to Insider's request for comment.