The leader of the Pakistan People's Party has condemned the alleged "inhuman torture" of two Christians by police in Lahore.

Bilawal Bhutto Zardari, party chairman, said the human rights abuses against the Christians could not be tolerated.

"We are torchbearers of struggle for human rights in Pakistan and any inhuman treatment or torture to fellow citizens will be vehemently resisted," Zardari said in a statement.

The victims, Faraz Masih, aged 30 and Doya Masih, aged 40, were picked up by the investigation wing of the Lahore's Shalimar police and suffered "brutal" torture, according to the statement.

The Pakistan People's Party said: "While carrying out the investigations the Lahore police hung one of the men upside down with a bunk and tortured him inhumanely. The other was stripped naked and tortured."

Zardari, the only son of former president Asif Ali Zardari and the late Prime Minister Benazir Bhutto, said those involved in this vicious form of torture should not go scot-free and strong action should follow to ensure such incidents do not happen again.

He said Christians, who are a small minority in Pakistan, are "equal citizens of the country" and any injustice or brutality to them or other citizens of the country could not be tolerated.

The Nation reported that the two victims are fighting for their lives in a private clinic.

They were picked up by police in connection with a mugging case last week. Four police officers were suspended after a relative of one of the victims released photographs.