Pakistan must overhaul laws to ban forced conversions to Islam, which are leading to rape or other abuse against hundreds of non-Muslim girls each year, a religious freedom group said Wednesday.

The Movement for Solidarity and Peace, which campaigns against religious violence in Pakistan, said that forced conversions generally involve the abductions of girls or young women who are then converted to Islam and married.

The girls are often raped or beaten and, when the family complains to police, the abductor responds that the girl has willingly converted, the group said in a report.

An estimated 100 to 700 Christian girls and at least 300 Hindu girls undergo such conversions in the overwhelmingly Muslim nation each year, the group said.

"These trends threaten religious freedom and public safety for all people in Pakistan," the group's director of advocacy, Amber Jamil, told a congressional briefing in Washington. 

The group also called for more funding for the government to enforce laws and for a study to look more closely at the frequency of forced conversions across Pakistan.

Pakistan has been torn by religious violence in recent years. Human Rights Watch said that 400 Shiite Muslims were killed in targeted attack across Pakistan in 2013.

A leader of the Pakistani Christian community, Peter Jacob, told the briefing that international pressure could help persuade the Islamabad government to do more to protect religious minorities.

Jacob voiced alarm about a rise in violence despite reforms at the official level, including the abolition of separate electorates for religious minorities.

"It seems that violence has become self-generating," he said.

"In a kind of economy that has investment in violence, in hatred and in religious intolerance, these elements continue to grow beyond (what the) state can control," he said.