HUSSAIN KHAN WALA, Pakistan — Pakistani officials have initiated an investigation into allegations that a gang of men sexually abused more than 200 children and sold videos of the abuse.

The accusations have rocked the country, drawing the attention and condemnation of human rights activists and politicians in a case that involved subjects long considered taboo here.

At least 280 children under the age of 14 from three villages in eastern Punjab Province were said to have been subjected to sexual abuse by a gang of 15 men, who made videos to extort money from the children and their parents. Seven of the accused have been arrested, police officials said Sunday.

The accusations of abuse started trickling out last month as victims began to report it to the police, and last Tuesday, hundreds of residents staged a protest, accusing the police and local politicians of protecting the gang members and ignoring the accusations. Some of the protesters clashed with the police, and dozens of people were injured, including several police officers.

On Saturday, details of the abuse were carried by The Nation, a Lahore-based English-language newspaper, which reported that the gang members had drugged and intoxicated their victims, some as young as 6, and had recorded hundreds of videos. Some of the children stole jewelry and money from their parents to pay the men to stop them from making the videos public, according to the reports. The newspaper said many of the videos were sold to buyers and pornographic websites overseas.

The coverage prompted an outpouring of outrage on social media, especially on Twitter.

Pedophilia remains a taboo subject in Pakistani society. Human rights activists say that child abuse is rampant in the country and that homeless children, as many as 1.5 million according to some estimates, are particularly vulnerable.

However, provincial officials in Punjab played down the scale of the abuse and said that only seven cases had been registered by the police so far and that they were in possession of only 30 videos.

Most of the victims and gang members are from Hussain Khan Wala, a dusty farming village in the Kasur District of Punjab Province, near the border with India and about an hour’s drive from Lahore, the provincial capital.

“This group was active since 2007 when they were school students,” Shahzad Sultan, a senior police official said in an interview on Sunday, referring to the suspects. He said most of the videos involved consensual sex between teenagers.

Local police officials say the allegations became public only after a land dispute arose between two rival groups in the village. Mr. Sultan said that the videos of consensual sex were being used now as part of an effort by one party in the dispute to discredit or intimidate members of the other group with accusations of child abuse. “The videos are old,” he said.

The man identified as the main suspect, Haseem Amir, said in an interview that his uncle had bought the land under dispute now and that members of another family who opposed the sale were now accusing him and his friends of child abuse.

The seven suspects who were arrested are ages 16 to 25. Mr. Amir, 25, denied that he was involved in blackmail and extortion. “We made some mistakes while we were teenagers in school,” he said, alluding to the sex videos. “We used to record videos and share with one another just for fun.”

But Muhammad Ashraf, the father of one of the accusers, who filed a complaint to the police on Sunday, said his son, 20, was abused as a student five years ago, but did not tell the family at the time.

After video clips surfaced about two months ago, “we came to know about it,” Mr. Ashraf said.

“My son was disturbed and sad,” Mr. Ashraf said. “He asked us to lodge the case. He used to steal money and some valuables, and says he used to give it to the blackmailers.”

In one video, a boy is seen crying after he is sexually abused, and tries to cover his face with a hand to hide from the camera. In another video, a man orders a boy to smile as he films him while the boy is abused.

A senior police official, who spoke on the condition of anonymity for fear of offending local sensibilities, said the case involved a “mixture of social deviants” and behaviors that reflected changes in Pakistani society. “Such acts of teenage homosexuality are becoming common practice,” the officer said.

Opposition politicians said over the weekend that they planned to take up the issue of child abuse in Parliament on Monday.