Patna: A video showing four men raping a 14-year-old girl in Nalanda district went viral on social media on Saturday night, the fifth such clip in the past one-and-a-half months in districts under the jurisdiction of the Patna police zone.

Police said the girl was raped in an abandoned building at Ahiyapur village under the jurisdiction of Sarmera police station. She had gone to meet her boyfriend after being scolded by her mother over the affair.

She later told the cops that she had met Vikas Kumar at Sarmera bus stand. He took her to the house where three of his friends arrived and all four took turns to rape her. They recorded the crime on a mobile phone and uploaded it online. The video prompted the police to swing into action.

The girl's family lodged a complaint with the Women's police station on Sunday. All four accused were arrested.

Inspector-general (Patna zone) Nayyar Hasnain Khan expressed concern over the trend of rape videos. "This is a serious matter and police will certainly take stringent action against those involved in circulating the videos," he said.

Sarmera police station house officer (SHO) Uday Kumar said: "We have written to the superintendent of the hospital to verify the age of the accused to ascertain whether any of the four culprits was a minor. Prima facie, they appeared to be above 18 years of age."

This was the second rape reported from Nalanda, chief minister Nitish Kumar's home district, in a week.

On Wednesday, a girl was raped in the presence of her relative near Vanganga in the district. The girl was returning home to neighbouring Nawada district's Hisua police station area from the Malmas fair organised at Rajgir in Nalanda on her brother-in-law's motorbike when they were waylaid and the girl raped - almost a copy of the Gaya gang-rape where a mother and daughter were assaulted.

"The two accused had waylaid the girl's brother-in-law, assaulted him and then raped the girl," said the investigating officer.

The police arrested one person, Devbrat Yadav, who is learnt to have confessed to the crime and also disclosed the name of his accomplice. An officer posted at Nalanda Women's police station said raids were underway to arrest Devbrat's associate, Pintu alias Bhola Yadav.

Last week, a girl was molested by a group of youngsters while she was returning home from tuition with a classmate in Hilsa police station area of Nalanda. A complaint was lodged after a video went viral on social media.

Leader of Opposition Tejashwi Prasad Yadav tweeted on Sunday: "Big Breaking : Today another Gang-rape in Bihar, that too in CM's home district. Feeling ashamed as a Bihari because BJP led Nitish govt has turned Bihar into a rapist state. From where predators getting moral support & repeatedly committing such crimes. What r u doing Mr. CM?"