Image caption Hazif Abdul Hamid and Sabir Ali have been linked to the proscribed group

Police Scotland is to investigate alleged links between two prominent Muslim leaders and a banned sectarian group in Pakistan.

A BBC investigation has found that Sabir Ali, head of religious events at Glasgow Central Mosque, was president of Sipah-e-Sahaba (SSP).

This is a political party now proscribed by the Home Office.

Links to the group have also been made to Hafiz Abdul Hamid from the Polwarth Mosque in Edinburgh.

Glasgow Central Mosque said it would not remove Mr Ali from his role until the links were proved.

But it said it condemned terrorism of any kind.

It is understood Mr Ali denies the allegations.

Mr Hamid declined to comment.

Deadly attacks

The BBC has obtained evidence that both men continued to be involved with the organisation after it was banned in the UK in 2001.

It is not clear whether the two men are still involved.

Sipah-e-Sahaba is a militant anti-Shia political party formed in Pakistan in the 1980s.

The group and its armed off-shoot, Lashkar-e-Jhangvi (LeJ), have accepted responsibility for deadly sectarian attacks against Shia Muslims and other religious minorities in Pakistan.

It has links to the Taliban and Al-Qaeda and was banned by the Home Office in 2001 - and in Pakistan one year later.

Image caption A bombing in Quetta, Pakistan, in 2013 was linked to sectarian tensions

An official UK government document describes the group's purpose: "The aim of both SSP and LeJ is to transform Pakistan by violent means into a Sunni state under the total control of Sharia law.

"Another objective is to have all Shia declared Kafirs [non-believers] and to participate in the destruction of other religions, notably Judaism, Christianity and Hinduism."

The BBC has obtained copies of the group's in-house magazine, Khalifat-e-Rashida, spanning the years both before and after its proscription.

They show that both the men in Scotland used their mosques to hold events in SSP's honour and further its teachings.

And they show that, in the case of Polwarth Mosque in Edinburgh, financial support was provided to the group after it was banned.

Key link

Donations from abroad are believed to be a key funding source of SSP.

Sabir Ali, also known as Chaudhry Sabir Ali, is a member of the executive committee at Glasgow Central Mosque - Scotland's largest - where Sunni Muslims of Pakistani origin are the largest group.

He has held the position of Ishat-e-Islam, or leader of religious events, for a number of years, making him a key link between the Imams and the mosque community.

Documents obtained by the BBC list him as "President of SSP Scotland".

In October 2003, after the group was banned, an article in Khalifat-e-Rashida describes a memorial service at Glasgow Central Mosque for the former leader and co-founder of SSP, Azam Tariq, who had been assassinated in Pakistan that same month.

At the meeting, the magazine says, a man named Chaudhry Sabir told those attending that Azam Tariq had "won the hearts of the Muslim world" and that "the enemies of Islam killed him" before vowing to continue his mission.

Image caption Sipah-e-Sahaba was banned in Pakistan and in the UK

That same year, in July, SSP's armed off-shoot, Lashkar-e-Jhangvi (LeJ), admitted responsibility for an attack at a mosque which killed 50 Shia Muslims.

One month before the meeting, an article in the magazine carries an advert to commemorate the sister of Chaudhry Sabir Ali after her death in Pakistan.

Chaudhry Sabir Ali is described as the "convenor of Ishat-e-Islam" at Glasgow Central Mosque.

In some areas of Pakistan, Chaudhry is given as a title of respect or eminence.

According to the magazine, before his death in 2003, Azam Tariq had been hosted by Sabir Ali in Glasgow on a number of occasions, as had another SSP leader, Zia ur Rehman Farooqi.

'Serious allegations'

Lawyer Aamer Anwar has called for reform at Glasgow Central Mosque.

"These are very serious allegations," he told the BBC. "There needs to be an investigation and the individuals concerned are entitled to due process."

"But the attitude almost seems to be that you can have a cut-off line, that if it's in Pakistan it doesn't really concern us over here, but it does.

"Even worse than that, is the impact on the community to be tagged with an organisation that regularly engages in murder and terrorism in Pakistan."

A member of the mosque community, who did not wish to be named, told the BBC: "We have to do something. This is all unacceptable. This is un-Islamic - this is not the Islam I know, that I've been brought up with."

It is understood Mr Ali denies the allegations.

Image copyright Thomas Nugent Image caption Glasgow Central Mosque said it condemned terrorism and extreme views

In a statement Glasgow Central Mosque said: "Islam is a faith of peace and we openly reject and condemn terrorism and extreme views of any kind."

"Glasgow is a proud beacon of how Muslim communities can engage with the wider society and The Central Mosque will continue to take a lead in promoting integration."

Glasgow Central Mosque has recently been the subject of controversy.

Last week the BBC and The Herald revealed that the lead imam at Glasgow Central Mosque had praised Mumtaz Qadri, who was executed last month in Pakistan after murdering the governor of Punjab over his opposition to the country's blasphemy laws.

Imam Habib Ur Rehman said his words had been taken out of context and that he was voicing his opposition to the death penalty.

The Office of the Scottish Charity Regulator (OSCR) is currently investigating the financial situation at the mosque after seven members of its executive committee resigned amid claims they had been threatened and intimidated by more conservative figures at the mosque.

Those claims were denied by those who were accused.

Preaching tolerance

Mr Anwar said: "There is no point preaching religious tolerance, talking about unity of the communities, condemning terrorist attacks, and then to be found that, privately, you are involved in supporting or showering praise on individuals who actually commit atrocities."

"Where extremism is exposed, we have to unequivocally condemn it."

Hafiz Abdul Hamid is the founder and leader of Idara Taleem-ul-Quran mosque in Edinburgh, often referred to as Polwarth Mosque.

The documents obtained by the BBC list him as the leader of Sipah-e-Sahaba in the UK in 2004.

In 1999, there was an attempt at the Court of Session in Edinburgh by other figures at the mosque to remove him for his post.

The judge found that he was the UK president of SSP but that as the organisation was legal in this country at that time he could not remove him from the charity which runs the mosque.

The BBC can reveal that Hamid, who claims to have memorised the Quran, continued in his role and continued his ties to SSP past the date that it was banned.

In January 2004, he gave an interview to Khalifat-e-Rashida in which he says: "The party work should continue in all circumstances. However, we should try to get SSP restored so that the religious work can continue with the same zeal and fervour."

"This party will work for the political dominance of Islam."

Deobandi movement

His mosque also paid for a series of adverts in the magazine after the group was banned, and a November 2003 edition details a phone call in the mosque in which Azam Tariq's brother Alam thanks the mosque for its financial support.

Mr Hamid did not respond to numerous requests from the BBC for comment.

SSP is part of the Deobandi movement, which espouses an orthodox interpretation of Islam and whose followers include the Taliban.

Since its formation, the group has waged a campaign of sectarian violence in Pakistan, moving between attacking other Muslims who it considers to be heretics or other religious minorities.

In 2013, SSP's armed wing Lashkar-e-Jhangvi (LeJ), named after one of the organisation's founders, claimed responsibility for a bombing targeting Shia Muslims in the Pakistani city of Quetta, which killed 100 people.

The group is said to have killed hundreds of Shias in the country, mainly in the Eastern province of Punjab, where at the weekend a bombing attack on Christians celebrating Easter killed more than 70 people, including children.

Christians have also been targeted by SSP in Punjab.

You can hear more about the BBC's investigation into the Deobandi movement on Radio 4's series "The Deobandis" which will be broadcast on Tuesday 5 and Tuesday 12 April at 09:00 BST.