A Kenyan illegal alien is charged with capital murder in connection to the alleged robberies and murders of 12 elderly women.

Police in Texas originally arrested 46-year-old Billy Chemirmir, a Kenyan national living illegally in Dallas, for the alleged murder of an 81-year-old woman. He has since been connected to the alleged murders of at least 11 additional elderly. Officials say Chemirmir stole jewelry and other valuable items from the victims, the Associated Press reported.

A grand jury in Dallas County handed down six indictments earlier this week, Dallas County District Attorney’s Office spokeswoman Kim Leach told the AP. The victims in these murders range from 76-94.

At least five indictments have been handed down from a grand jury in neighboring Collin County.

Dallas police initially arrested Chemirmir in connection to the homicide of 81-year-old Lu Thi Harris in March. During an investigation into her murder, police in Plano, Texas, say they found evidence linking the Kenyan man to the Dallas homicide while investigating an attack on a 91-year-old woman. Plano is located just north of Dallas in Collin County.

Investigators say the Plano woman passed out after being smothered with a pillow. However, she did not die from the attack. Police identified Chemirmir’s license plate from the apartment complex. Investigators found him and tailed him until they found him throwing a jewelry box into a trash bin. The Plano woman reported that her attacker stole a box containing her jewelry.

The woman told investigators Chemirmir, employed as a home healthcare worker, told her on the night of her attack to “got to bed. Don’t fight me,” the AP reported from an arrest affidavit. He then allegedly placed the pillow over her face and attempted to kill her.

Investigators are looking into suspicious deaths of about 750 unattended deaths of elderly women to try and find additional links.

Plano Police Chief Gregory Rushin said Chemirmir used his home healthcare experience “to his advantage in targeting and exploiting seniors, some of the most vulnerable people in our community,” the AP reported.

Chemirmir denies the charges, according to his attorney, Phillip Hayes. The attorney told the AP that “these charges came out of the blue.”

“They have circumstantial evidence that puts him in the area, but that’s as far as the evidence goes,” Hayes explained.

U.S. Immigration and Customs Enforcement officers also placed an immigration detainer on the Kenyan national who is reported to be in the U.S. illegally. It is not known if that is from illegal entry or a visa overstay.