The 14-year-old's mother said her daughter hanged herself after being humiliated by a teacher, Kenyan media reported.

Police used tear gas to disperse a crowd of about 200 parents protesting outside the school, reports said.

Kenya passed a law in 2017 to provide free sanitary towels for schoolgirls.

However, a parliamentary committee is currently investigating why the programme is yet to be rolled out across all schools.

The girl's mother said a teacher had called her "dirty" for soiling her uniform and ordered her to leave the class in Kabiangek, west of the capital Nairobi, last Friday.

"She had nothing to use as a pad. When the blood stained her clothes, she was told to leave the classroom and stand outside," the mother was quoted as saying in Kenyan media.

She said her daughter came home and told her mother what had happened, but then when she went to fetch water she took her own life.

Her parents reported the matter to the police but became frustrated by an apparent lack of action, the Daily Nation reported.

Together with other parents they staged a protest outside the school on Tuesday. Police moved in and made five arrests when the demonstrators blocked a road and pulled down the school gate, reports said. The school has since been closed.

Regional police chief Alex Shikondi said the circumstances of the girl's death were being investigated.

The school's headteacher has declined to comment.

In Kenya, as in other countries, many girls cannot afford sanitary products such as pads and tampons.

A UN report in 2014 said that one in 10 girls in sub-Saharan Africa missed school during their period.

Some girls reportedly lose 20% of their education for this reason, making them more likely to drop out of school altogether, the report said.