At least one British-born Hindu is believed to be among the dead in the Gujarat temple massacre and that death toll may rise.

More than 30 people are believed to have been killed when Islamic militants opened fire on worshippers inside the 23-acre Swaminarayan Temple complex in the state capital, Gandhinagar.

The militants were later shot dead by Indian commandos.

Soldiers stand guard outside the temple in Gujarat

Foreign Secretary Jack Straw said: "I am horrified by this attack on innocent civilians.

"I strongly condemn all acts of terrorism. Religion can never be an excuse or justification for violence. My thoughts are with the victims and their relatives."

Girish Patel, a spokesman for the Swaminarayan Hindu temple in Neasden, north London, told BBC News Online the deceased, whom he did not name, was born in the UK but had moved back to India.

He said a continuous prayer vigil was being held at the Neasden temple, where security had been stepped up by posting police-trained guards on all doors and conducting bag and body checks.

A Foreign Office spokesman said he was not able to confirm the deaths of any British-born Asians.

Religion can never be an excuse or justification for violence.

Jack Straw

There are fears of communal rioting in India following the massacre and the tension could also spread to the UK.

Mr Patel, who helped in the construction of the Gandhinagar temple, urged all Hindus to refrain from retaliation against Muslims.

He told BBC News Online: "People are burning inside but you have to let it go. That is what makes us proud Hindus."

A priest looks on as Indian ministers tour the scene

Mr Patel said his message to all Hindus was: "Under no circumstances should you make a judgement. Hang on to your beliefs. We must prevent further loss of life."

He said the death toll at Gandhinagar could have been much worse considering the thousands of people who visit the site.

Mr Patel described it as a "spiritual Disney-type resort" sprawled over 23 acres and he said checking the bags of every visitor would have been impractical.

He said that, unlike the temple at Ayodhya - which was said to be the birthplace of the Hindu god Lord Ram, Gandhinagar was quite a new complex and had no historical significance.

But he said: "It is still sacrilege to shoot indiscriminately into a temple.

We don't care who did it. They don't represent Islam or anybody who is rational. They are just a criminal element,

Girish Patel Temple spokesman

"We don't care who did it. They don't represent Islam or anybody who is rational. They are just a criminal element," said Mr Patel.

He said staff and volunteers at the Neasden temple would be administering to the physical and spiritual needs of all those affected by the massacre.

Anyone who is concerned about relatives who may have been in the complex can ring the Foreign Office helpline on 020 7008 0218.