A wedding celebration turned into a horror story when a 21-year-old bride-to-be was burned with acid, allegedly by the groom’s girlfriend in northeast Delhi’s Gokalpuri area, police said on Wednesday.The victim, who was set to be married on April 19, along with her sister, is under treatment for burns on her eyes, face, neck and hand at Guru Teg Bahadur (GTB) Hospital, a police source said.The incident took place around 12.30 pm on Tuesday at the victim’s house in Indira Vihar, where a “mehendi” ritual was under way. The accused arrived at the house, joined the celebrations without raising suspicion, and attacked her when she got the chance.”Initially, we got to know that the two women were conversing normally, even discussing how to apply the henna, when the situation took a sudden turn,” said the police source.The woman opened a bottle, purportedly carrying acid, with a quick movement, and threw it in the bride’s face and then tried to attack her with some object.The house erupted in chaos, and family members rushed to help the bride, who screamed in pain. The attendees caught the 26-year-old woman and called the police.Doctors have placed the victim under observation and her condition is being closely monitored.Initial probe suggests that both women are neighbours and the manner in which the accused gained entry into the house and concealed the acid in a bottle hints at a premeditated attack.”The accused is a neighbour of the victim and had been in a relationship with the groom-to-be for the past five years,” said the source.The alleged attacker was arrested and produced before a local court, the source said. She was sent to judicial custody.By the time a team from the police station reached the house, the woman had already been taken to the hospital.”Investigations revealed that the victim’s marriage had been fixed with a man and the wedding was scheduled in the near future. However, the accused woman, who was reportedly in a relationship with the same man, was opposed to the marriage.”Driven by jealousy and anger, the accused allegedly attacked the victim by throwing acid on her,” the police said.The police are trying to locate the source of the acid used in the crime.