A man who allegedly poisoned his ex-wife, his pregnant lover and her grandmother is said to have used a syringe to inject the deadly substance thallium – often used as a rat poison – into his victims, according to the police.

Thallium is an extremely toxic compound and the alleged killings took place in the town of Huerth, which is on the outskirts of the city of Cologne.

The accused, who has only been named as Manuel H., 41, due to strict local privacy laws, has been in custody for five weeks and the public prosecutor’s office has now alleged that the hygienist poisoned the three women with thallium, which is commonly used as a rat poison, by injecting it.

Two of the women died from the poisoning, with it now being revealed that the police found a syringe when they searched the man’s house at the end of November 2021.

It is alleged that the man targeted his family members out of greed, in the hopes of inheriting property which included for example a large brick house in Huerth.

The house was owned by Helene G., the grandmother of his current girlfriend, with the old lady dying at the age of 92 on 1st April 2021 from what is now identified by investigators as a fatal dose of thallium.

After her death, Manuel H., and his girlfriend Yvonne K., 36, a high school teacher, moved into the house but suspicions began to grow regarding Manuel H., so he allegedly poisoned his pregnant partner with the toxic compound.

The woman and her unborn baby have been in hospital for weeks. Their current health condition is unclear.

But police think that Manuel H.’s girlfriend and her grandmother may not be the 1st to have allegedly been poisoned by him.

He used to live in a house in Leverkusen-Hitdorf, which is a city in the western German state of North Rhine-Westphalia, along with his wife, who has been named as Tina H., who was also high school teacher and who died in May 2020 at the age of 35 after being reportedly poisoned – with thallium.

Manuel H. is suspected of double murder. Martin Buecher , 43, his lawyer, said: “My client will not comment on the matter.”