Washington - United States President Barack Obama on Wednesday called Indian Prime Minister Manmohan Singh to offer his condolences over the shooting at a Sikh temple in Wisconsin, in which six people - including several Indian nationals - were killed.

White House spokesperson Jay Carney said Obama paid tribute to the contribution of the Sikh community in the United States and that the two leaders spoke of their shared commitment to tolerance and religious freedom.

The killings occurred during Sunday services when Wade Michael Page, a singer in a neo-Nazi punk band, burst into a Sikh temple in Oak Creek, Wisconsin, and opened fire on worshippers with a 9mm handgun.

“The president held a phone call, a conversation with the prime minister of India. The president expressed his condolences to the prime minister because as you know, several of the victims of the shooting in Wisconsin were Indian nationals,” Carney said.

“The two leaders spoke about their shared commitment to tolerance and religious freedom,” he added.

Obama placed the call from his presidential aircraft as he flew from Washington to Colorado at the beginning of a two-day campaign trip.

The FBI said earlier on Wednesday that Page, 40, killed himself with a gunshot to the head on Sunday after being shot in the stomach by a police officer called to the scene.

US investigators have yet to establish a motive for the killings, but they are looking into Page's links with white supremacist hate groups. - AFP