Outrage over an attack on a woman who was dragged through the streets of a north German town behind a car with a rope tied around her neck has prompted hundreds of people to attend a vigil for her.

The 28-year-old woman is in a coma in a critical condition in hospital in Hamelin following the incident on Sunday evening.

Her former partner, a 38-year-old man, handed himself in to police and is in custody facing a potential charge of attempted murder. He and the woman are believed to be of Kurdish origin.

The woman was dragged along the road for about 250 metres. Her two-year-old son was reportedly in the back of the car at the time.

Locals attending the vigil held up placards reading “incredible” and “stop violence against women”.

The brother of the victim and his children hold up a signs with the words ‘why?’ and ‘unbelievable!’ Photograph: Julian Stratenschulte/EPA

Hamelin’s mayor, Claudio Griese, addressed the crowds by saying that acts of violence were an unfortunate part of society but that Sunday’s incident had been particularly horrific.

“No one could have imagined that such a barbaric act that reminds us of executions of the middle ages was possible in a town such as Hamelin,” he said.

He said the vigil, which was attended by members of the victim’s family including her brother and his children, sent the message: “Violence has no place in this town.”