A healthcare worker has been charged with the murder of 12 elderly women by smothering, and is being investigated for any potential links to 1,000 more unexplained deaths.

Billy Chemirmir, 45, of Texas is accused of murdering multiple elderly women who lived in Dallas and Collins counties with a pillow, and subsequently robbing them.

In March of 2018, Mr Chemirmir was charged with capital murder in the death of an 81-year-old woman, Lu Thi Harris, leading to his arrest.

Mr Chemirmir has also been accused of two counts of attempted capital murder for attacking two women. One of the two women, a 93 year-old who was a resident of the Parkview Elderly Assisted Living facility in Frisco, Texas, had reported the incident to police.

She described how a well-dressed man had knocked on her door, claiming to be a maintenance worker. When she responded that she did not require any work done, he forced his way inside and "knocked her from her walker to the floor", as reported by Dallas News.

Mr Chemirmir worked as a nurse in his native country of Kenya, but appears to not have been legally working in healthcare in the US. Court records indicate that Mr Chemirmir posed as an employee at the Edgemere Retirement Community in Dallas under the alias “Benjamin Koitaba”.

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Plano Police Chief Gregory W. Rushin said Mr Chemirmir used “health care experience to his advantage, targeting and exploiting seniors”, something Mr Rushin called “disturbing’.

Authorities plan to review the unattended deaths of hundreds of elderly women in the area, including those who were previously thought to have died from natural causes to investigate any potential ties to Mr Chemirmir.

Recently, the accused killer has been newly indicted in six deaths of elderly women from 2016 to 2018: Phyllis Payne, aged 91, Phoebe Perry, aged 94, Norma French, aged 85, Doris Gleason, aged 92, Rosemary Curtis, aged 96, and Mary Brooks, 87. He has also been charged with five other murders, of which the victims have yet to be named.

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