We don't yet know what motivated the shooter: Obama

If the ethnicity of those attending the gurudwara in Wisconsin, where six persons were shot dead two days ago, turns out to be the reason behind the massacre, then Americans should "immediately recoil against those kinds of attitudes," United States President Barack Obama has said.

"If it turns out, as some early reports indicate, that it may have been motivated in some way by the ethnicity of those who were attending the temple, I think the American people should immediately recoil against those kinds of attitudes," he said on Monday.

Obama also raised alarm over the regularity of such incidents in the US.

"I think all of us recognise that these kinds of terrible, tragic events are happening with too much regularity for us not to do some soul-searching and to examine additional ways that we can reduce the violence," he said.

"I think it will be very important for us to reaffirm once again that, in this country, regardless of what we look like, where we come from, who we worship, we are all one people, and we look after one another and we respect one another," he said.

"We don't yet know fully what motivated this individual to carry out this terrible act," said the US President in response to a question at the Oval Office during the signing of the Honoring America's Veterans and caring for Camp Lejeune Families Act of 2012.

Awaiting the outcome of a full investigation of the tragic incident, Obama said on Sunday he had the chance to speak to the Governor of Wisconsin, the city Mayor, as well as leaders of the Sikh community in Oak Creek.

"All of us are heartbroken by what has happened. And I offered the thoughts and prayers not only of myself and Michelle but also for the country as a whole," said the US President.

"There are a lot of elements involved in it, and what I want to do is to bring together law enforcement, community leaders, faith leaders, elected officials of every level to see how we can make continued progress," he said.

The Federal Bureau of Investigation is working with local officials and they are still investigating what motivated this individual.

"And as we find out more, I suspect that not only the White House but others in Congress and at the local level will have more to say," he said.

Meanwhile, condolences continued to pour in from across the US.

Secretary of Homeland Security Janet Napolitano said her department will continue to provide any support necessary to the ongoing investigation.

"Our thoughts and prayers go out to those impacted by this tragedy, the Sikh community, and especially the family and friends of those killed or wounded," she said.

"America's Sikh community and all Americans mourn the loss of the six victims who perished in this senseless act of violence," said Senate Majority Leader Harry Reid.

"The ability to worship freely and without fear is a bedrock principle of our nation, and a threat to any religious community's freedom is a threat to all Americans that must not be tolerated," he said.

"We send a message of sympathy to the family and friends of the victims and ask colleagues in government and Americans across the country to join together and redouble our efforts to prevent gun violence," said New Jersey Senator, Frank R Lautenberg.

"We must end these senseless acts of violence and join together as a community of diverse cultures and faiths, striving towards peace, understanding, and a stronger and unified America," said Dr Ami Bera, an eminent Indian American and a Congressional candidate from California.

The chairman of the US bishops' Committee on Ecumenical and Inter-religious Affairs expressed the bishops' prayerful solidarity with the Sikh community following the August 5 shooting at the Sikh Gurudwara.

"In this time of grief, we Catholics mourn with our Sikh brothers and sisters," said Bishop Denis Madden, auxiliary bishop of Baltimore. "The US bishops stand with the Sikh community and reject all violence, particularly violence inflicted out of religious intolerance.

"We are especially saddened that this horrendous act was carried out in a house of worship against people joined together as a family to worship God," he added.

Observing that the Sikhs living in the US are peace-loving, active, law-abiding citizens and very much a fabric of the American society who have contributed immensely towards the economy, the Sikh Art & Film Foundation deplored the senseless acts.

"Our thoughts and prayers are with all of the victims and their families in the wake of this horrible tragedy. We are also extremely grateful to the brave officers of the Oak Creek Police Department and other first responders who put service above self to protect the members of their community," said Tejinder S Bindra, president of SAFF.

"This was an attack not just on the Sikh community, but against all humanity," he added.

"With our common heritage and history, American Sikhs and Hindus share a unique bond unlike any other two religious communities. We pray that the souls of the deceased find peace," the Hindu Swyamsevak Sangh, USA, said in a statement.

The Islamic Society of North America said it was deeply saddened by the news.

"Our thoughts and prayers go out to the families of those who lost their lives and to those who are suffering from critical injuries," it said.

"ISNA is grateful for the heroic police officers who risked their lives to put an end to the shooting, and prays for the swift recovery of the officer who was shot multiple times in the process," the statement added.

Meanwhile, the Council on American-Islamic Relations on Tuesday called for stepped-up police protection at Muslim institutions and other houses of worship nationwide after a fire destroyed a Missouri mosque that had previously been targeted by an arsonist and after the deadly shooting at a Sikh temple in Wisconsin.

"These disturbing incidents point to the urgent need for increased police protection for Muslim and Sikh houses of worship nationwide," said CAIR national executive director Nihad Awad.