A Kenyan living illegally in the US has been charged with killing at least 11 elderly women, and stealing their jewellery and valuables in Dallas, Texas.

Billy Chemirmir was previously arrested in the death of an 81-year-old woman, ABC Fox Montana has reported.

The 46-year-old was indicted on Tuesday on six counts of capital murder in the deaths of women aged 76 to 94.

Chemirmir, according to the Journal Star, has been in custody since March 2018 over the death of Lu Thi Harris, 81, also from Dallas.

Police found evidence linking him to the Harris murder when he was being investigated in the Dallas suburb of Plano for suspicious death and suspicious person calls.

According to the Lincoln Journal Star, the break in the case came when Chermirmir forced his way into the apartment of a 91-year-old woman in March last year.

He allegedly asked the woman to “go to bed. Don’t fight me,” according to an affidavit filed in Collin County.

The Lincoln Journal Star reported that Chermirmir smothered the woman with a pillow until she was unconscious after which he stole her jewellery.

After the paramedics revived her, she told them her jewellery box had been stolen by her attacker.

Police then identified Chemirmir from a number plate. They traced him days later and watched him throw a jewellery box into the bin.

The police traced the box back to Harris.

According to the Plano police chief, Chermirmir was using his healthcare experience “to his advantage in targeting and exploiting seniors, some of the most vulnerable people in our community."

According to ABC Fox Montana news reports, police were reviewing the unattended deaths of 750 elderly women for possible links.

Phillip Hayes, Chermirmir’s attorney, said the charges from this week were a surprise and there has not been time to review them.

“These cases came out of the blue and I don't have any information on them yet," he said.

According to the Lincoln Journal Star, Chermirmir's lawyer says he has denied involvement in the murder of Harris since day one.

"They have circumstantial evidence that puts him in the area but that's as far as the evidence goes," Hayes said.

Chemirmir is also being held on charges of being in the country illegally.

- The Star