Militants stormed two mosques belonging to the minority Ahmadi Islamic sect at Lahore in Pakistan taking a number of people hostage.
The Ahmadis, also known as Qadiani, have tens of thousands of followers in Pakistan. Human Rights groups say the sect has long been persecuted in Pakistan and has remained the target of sectarian attacks.
Founded by Mirza Ghulam Ahmad, who was born in 1838, the Ahmadi sect has a number of unique views including that Ahmad himself was a prophet and that Jesus died aged 120 in Jammu and Kashmir.
A website for Ahmadis says the movement -- headquartered in the UK now -- spans over 195 countries, with membership exceeding tens of millions. They claim they are the only leading Islamic organisation to categorically reject terrorism in any form.
They often come under prosecution and torture in Pakistan because of their sharp differences with Islam. The Ahmadis have often been targeted by radical Sunni groups in the past.
According to BBC, at the core of their conflict with mainstream Muslims lies their belief that the founder of the sect was a prophet.
The Ahmadis insist that he was not a "law-giving" prophet and his job was only to propagate the laws enunciated by Islam's Prophet Mohammad. But few among the Muslim mainstream are willing to accept this argument.
Throughout the first half of the 20th century, the issue of their faith kept being raised before different courts at the district level. In many such cases, local courts ended up declaring them non-Muslims.
In 1974, under severe pressure from clerics, Pakistan's first elected prime minister, Zulfikar Ali Bhutto, introduced a constitutional amendment -- known as the Second Amendment -- which declared Ahmadis non-Muslims.
In 1984, Pakistan's military dictator, General Zia-ul-Haq, brought in a new law that barred Ahmadis from reciting the Kalima (the first proclamation of Islamic faith), from calling their places of worship as mosques.
The movement's main object was to defend and propagate Islam globally through peaceful means, to revive the forgotten Islamic values of peace, forgiveness and sympathy for all mankind and to establish peace in the world through the spiritual teachings of Islam.
Ahmadis consider themselves Muslims and claim to practise Islam in its pristine form; however, Ahmadiyya views on certain beliefs in Islam have been controversial to mainstream Muslims since the movement's birth. Many mainstream Muslims do not consider Ahmadis to be Muslims, citing in particular the Ahmadiyya viewpoint on death and the rituals they perfoem after death.
Recently, Ahmadis were in the news in the sensational killing of Inter Services Intelligence officer Khalid Khwaja, who was kidnapped and killed while on his way to Waziristan apparently to make a documentary film on Taliban. A week later, a tape was leaked, where a militant commander was talking to well-known journalist Hamid Mir.
In the tape, the journalist is heard accusing Khwaja of being a CIA agent and working for Ahmedis as also of having played a 'dirty' role in the Lal Masjid episode in July 2007.
According to Pakistan's influential newspaper Dawn, Pakistan is the only Muslim state to have declared Ahmadis non-Muslims.
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