Police in the Taiwan capital Taipei arrested a man on Monday (March 28) who is suspected of beheading a four-year-old girl on the street outside a metro station, according to local media.

In what appears to be a random attack, a man attacked the girl with a knife before being wrestled to the ground by passers-by.

"When I realised or when I once again came to the crime scene, passers-by had already suppressed the killer down on the ground and called the police officer. In the meantime, my daughter was not where she should have been, or next to her bicycle, but lying on the ground," said the girl's mother.

The suspect was attacked by an angry mob as he was moved outside of the police station in Taipei.

The Taiwanese Central News Agency (CNA) reported that the police believe the attacker has a history of mental illness and drug abuse.