Islamic leaders and police have appealed for calm after a Muslim pensioner died following a race-hate attack in front of his three-year-old granddaughter.

Community leaders are fearful of revenge attacks after retired care home worker, Ekram Haque, 67, died on Monday, a week after he was beaten unconscious by a group outside the Idara-e-Jafferiya mosque, in Church Lane, Tooting.

Police confirmed his murder, and two assaults on other men standing outside the mosque, were racially motivated and appealed for witnesses who saw a group of black youths in the area.

They also linked the attack to another assault on an elderly Asian couple days before.

A police spokesman said they had increased patrols in the area, were using CCTV to monitor the situation and were looking at other attacks dating back to July.

Mr Haque and the other men were beaten by a group of five youths at 9.50pm on bank holiday Monday.

His son Arfan Haque, a consumer law advisor, said the family was completely devastated and his daughter, Miriam, was very shaken.

Speaking hours before his father’s death he said he understood frustrations in the Muslim community but appealed for Asian teenagers not seek revenge.

He said: “I want everyone to respect their religion.

“The Koran doesn’t condone revenge attacks, it is in the hands of the police now.”

A spokesman for the mosque, one of London’s oldest which attracts thousands of worshippers from south London, echoed the call.

He said: “We fail to understand what the reason behind the attack was, we heaven’t had a serious issue like this since the mosque was built in 1978.

“The community is acting responsibly but there is a lot of emotion and anger.

“It hasn’t reached the point of revenge attacks. We have been telling worshippers to stay calm and briefing them on what the police are doing. The Koran says there should be no revenge attacks . . . there’s obviously anger and anxiety but there’s no kind of revenge. The police have acted quickly and arrested people, so that helps.”

Tooting Sadiq Khan MP, visited Mr Haque hours before he died. He said: “The circumstances surrounding his death are still difficult for me to fully comprehend.

“It is crucial all the thugs responsible for his death are brought to justice. I would plead with anyone who has any information to come forward.”

A police source said: “We are treating these attacks as racially aggravated.

“I find it quite distressing how children can inflict terrible injuries on a man like that. Especially with a three-and-a-half-year-old, who was with her grandfather, watching on.”

Police appealed for a young boy on a bike and group of young women – who were white, black and mixed race – who were in the area at the time, to come forward.

Anyone with information should contact police on 020 8721 4205 or Crimestoppers anonymously on 0800 555 111.

• Four teenagers appeared in youth court on Tuesday. A 15-year-old, and two 14-year-olds from the Tooting area were charged with the murder of Mr Haque and two counts of ABH. The fourth boy, aged 12 was charged with conspiracy to commit GBH and two counts of assault.