Washington: Gurmej Atwal, one of the two Sikhs shot by unidentified assailants during their afternoon walk in Elk Grove township of California, has succumbed to his injuries, six weeks after the incident.

Atwal had been on a ventilator and unable to talk since the incident, which took place in the Sacramento suburb of Elk Grove. He died in hospital at 2 pm local time on Friday.

 "He's no more," Atwal's son Kamaljit Singh said. "First the kidneys stopped functioning, then the lungs and then brain. ... He was shot in the upper right chest, one bullet hit his lungs and the other effected pancreas, liver and intestines," he said. "My dad was going to be a key witness in the shooting. But from day one, he could not speak a word," Kamaljit said.

"Mr Atwal fought valiantly to recover after the shooting. We all hoped that he would be able to overcome the critical injuries. Now, we must rely on our faith as we support the family in making it through this difficult time," Darshan Mundy, Public Relations Officer for the Sacramento Sikh Temple said.

Atwal is survived by wife Balbir Kaur, daughter Talvinder Kaur and sons Kamaljit Singh, Balkar Singh and Sarbjit Singh. He lived with Kamaljit and his family at their home in Elk Grove.

The Sikh Community and a number of community organisations have come together to offer a reward of over USD 42,000 for information leading to the arrest of those responsible for the shooting.

Crime Alert Sacramento is offering an additional USD 10,000 reward if it is determined to be a hate crime.

According to family members, the victims were not robbed and had no enemies. However, they were wearing turbans at the time of shooting and had thick beards, leading police and community leaders to suspect that the attack was a hate crime.

78-year-old Atwal and his neighbourhood friend Surinder Singh, 65, were shot on March 4, sending shock waves among the Sikh community in the region. Singh had died on the spot.

(Agencies)