Chinese police have detained a man and a woman suspected of killing a man and posting his body parts to three different cities.

On January 7, staff at a logistics company in Qingdao, in China's eastern Shandong province, found a human torso in a box seeping blood but marked as carrying medicine.

Two days later, police in Beijing and Jiangyin, in eastern Jiangsu province, found a man's head and arms.

"The case is thought to involve a murder for love," report said.

The victim was believed to be the casualty of a love-triangle between a young employee of a logistics company and a prostitute.

The two allegedly conspired to kill the victim, a 50-year-old man, "because he had met with the prostitute", report said.

Closed-circuit television footage from a shipping company in Guangzhou, capital of southern Guangdong province, showed a man and a woman sending the packages, signing for them under the pseudonym "Song Deyuan", which means "sent far away".