Police in Binh Duong Province last Saturday detained four women, Pham Thi Thien Ha, 31, her mother Trinh Thi Hong Hoa, 66, Nguyen Ngoc Tam Huyen, 40, of Ho Chi Minh City and Le Ngoc Phuong Thao, 29, from the Mekong Delta province of Tien Giang.

The four were held to investigate the murder of two men whose bodies were discovered two days earlier, one entombed in concrete in a plastic water tank and the other embalmed in tea leaves, put in a water tank and covered with concrete.

One murder took place in a house in Ba Ria-Vung Tau Province, and the other in a rented house in Binh Duong, both around two hours from HCMC.

Ha, the leader of the group, has told the police that the four women, along with the two victims, Tran Duc Linh, 51, from the north central province of Nghe An, and Tran Tri Thanh, 26, from HCMC, rented a house in Ba Ria-Vung Tau for their religious practice in December last year.

While no information has been released on the sect, it appears that it was loosely based on qigong, which refers to a system of gentle physical exercises.

According to rules set by Ha, no member of the sect was allowed to eat, drink or go out of the house for 10 straight days during the practice session.

But Linh was not able to obey the regulations so he tried to escape halfway. He jumped out of the house from the second floor and suffered severe injuries. 

Instead of taking him to the hospital, Ha and the rest of the team brought him back into the house, and let him die. Later they put his body in an air-conditioned room for preserving.

A week later, the group moved to the rented house in Binh Duong along with Linh’s body.

It was Thanh who embalmed the body there with tea leaves, packed it in sponge, glue and silicon before putting it in a plastic tank that was then covered in concrete.

The group decided to keep it that way, so that nobody could track down the death of Linh.

But Thanh was haunted by what he had done and could not follow the practice anymore.

This made Ha angry. She decided to lock Thanh in a room and starve him so that he could have time and space to "repent his sins."

But as the rest of the group learned that Thanh could not "improve himself" to continue with the practice, they made plans to get rid of him.

Ha sent Thao to buy a battery and an electric actuator. They pretended to give Thanh an acupuncture, but electrified him instead, making him unconscious. Ha then strangled Thanh to death.

Three days later, the all-female group bought a plastic water tank, put Thanh's body in and filled it up with concrete.

The two murder cases were discovered on May 15 when a man who bought the house in Binh Duong was cleaning up the place to move in. He found the tank with Thanh’s body in the bedroom and had some workers break it in order to move it out.

Linh’s was found later by the police by the side of the house.

As police probed the case, the group moved to a hotel in Thu Dau Mot Town in Binh Duong.

A staff there identified and reported them to the police.

Ha used to study and work in Japan. She could communicate in English, Japanese and Chinese. After returning from Japan in 2015, Ha opened a coffee shop at a prime location in HCMC. The coffee shop reportedly did very well, but it was shut down in late 2017, investigation found.

One of Ha’s friends said that around the time that the coffee shop closed, Ha changed her lifestyle completely and repeatedly shared videos and photos related to a sect on social media. She told others that she had become a follower of that sect.

Ha told the police that she covered the cost for all activities from transportation to renting accommodation for the group.

In the seven-seat car that Ha owns, police found 30 ounces of gold, $20,000 and VND300 million ($13,000) in cash. Ha said she got the money from selling her house in HCMC.

Ha and the other three women are being investigated for murder.