Three Pakistani police officers have been transferred to other districts over accusations of negligence amid a deepening scandal over a paedophile ring alleged to have abused hundreds of children for nearly a decade,

officials say.

A prominent family in the central Punjabi village of Husain Khan Wala allegedly used guns, knives and axes to force children - some as young as five - to perform sex acts on video, which they then sold or used to extort money from the victims' families, villagers said.

This weekend, the prime minister pledged an investigation after Pakistani media covered protests by parents claiming that police in the district of Kasur had not investigated their complaints.

The officers were removed from their posts "for their negligence on the Kasur sex scandal", Nabeela Ghazanfar, a spokesperson for the provincial police, told Reuters news agency on Wednesday.

Rai Babar, the district police chief, and two deputy superintendents were reassigned out of the district. Police in Pakistan are rarely sacked.

Parents told Reuters that police had refused to register some complaints and treated some of the victims "like criminals".

The police have arrested 14 suspects so far. Seven cases have been registered against them for alleged sodomy, kidnapping and torture, Muhammad Amin, a police official, said.

The accused would be tried in an anti-terrorism court, Amin said. Law enforcement officials frequently use the anti-terror courts to bypass Pakistan's moribund judicial system.

On Monday, opposition politicians criticised the ruling party over the scandal in Punjab, the country's biggest and wealthiest province and the political heartland of the ruling party.

Shahbaz Sharif, Punjab's chief minister and the brother of the prime minister, said on Tuesday that he was "personally monitoring" the case.

"We will not let anyone involved in this incident escape the law and justice. All victims and their families will be provided every possible assistance to identify culprits without any fear," he said in a statement on his Facebook page.