Amarjit Singh is a priest at the Sikh Temple Modesto Ceres, around 160 kilometres east of San Francisco.

The priest of a gurdwara in California was allegedly assaulted on Thursday night in an apparent hate crime, media reports said on Friday.

The priest, Amarjit Singh, told local Fresno Bee newspaper that an intruder, who broke open the window to enter his home inside the gurdwara campus, punched him, asked him to go back to his country and yelled obscenities at him.

Amarjit Singh is a priest at the Sikh Temple Modesto Ceres, around 100 miles (160 kilometres) east of San Francisco.

The miscreant, who was wearing a mask, allegedly punched the priest in the neck. He shouted at him, saying "country, country, country, go back, go back, country," he told the daily. The attacker also yelled obscenities at him and had something in his hand to break the windows, he said.

Modesto City Councilman Mani Grewal, who is also a member of the gurdwara, described it as a hate crime. In a video, he said it looked like "this was an attack incited by hate, by bigotry".

"We have seen that this has been going on for a while now," Mr Grewal told Fresno Bee, adding that such incidents had increased in the last couple of years.

The local police, which has started an investigation into the issue, said it was too early to conclude that this was a hate crime.

Local Congressman condemned the incident. "I stand with my friends in the Sikh community at this terrible time. Every American -- regardless of faith -- should be able to practise their religion freely and without the fear of violence. This disgusting attack is not representative of who we are and we must find the person responsible," Congressman Josh Harder said.

"This is part of a larger pattern of hate against minority communities in the Central Valley. An attack on one minority community is an attack on all minority communities -- whether it''s Sikh, Latino, Muslim, LGBTQ, Assyrian or anyone else," he added.