Health experts have warned the health and social care system is "failing" young girls at risk of FGM

A baby girl born on Christmas Day in a remote region of Tanzania was subjected to female genital mutilation by her great-grandmother and died a few days later, police said.

The girl was born to a 16-year-old single mother in the Manyara region of northern Tanzania. Five days after her birth, her 70-year-old great-grandmother performed the ritual which led to complications and the infant died in hospital.

Francis Massawe, Manyara Regional Police Commander, told the Thomson Reuters Foundation on Tuesday the mother and great-grandmother had been arrested and a criminal investigation was underway.

FGM is illegal in Tanzania and campaigners say many communities are rejecting the harmful traditional practice.

However, the Network Against Female Genital Mutilation (NAFGEM) that works with communities in the Kilimanjaro and Manyara regions, said there was evidence families who were still cutting their girls were starting to doing it at younger ages.

"Girls used to be mutilated around the age of 10 years old and it was a traditional practice to prepare them for marriage," Francis Selasini, executive coordinator of NAFGEM, told the Thomson Reuters Foundation.

"Those who are still cutting are performing it on girls who are younger to avoid prosecution."

NAFGEM staff visited the baby in hospital and took the teenage mother to one of the NGO's shelters, but she was later arrested when the baby died, he said.

Campaigners said uneducated teenage mothers were coming under pressure to allow their baby girls to be mutilated.

"Some see FGM as a tradition that must be kept," Selasini said.

An estimated 200 million girls and women worldwide have been subjected to FGM. In Africa, it is thought that 3 million girls are at risk every year.

FGM often causes a host of health problems. In some cases girls may bleed to death or die from infections. Others may suffer fatal childbirth complications later in life.

Reuters