It was the worst one I've ever felt. The whole building was shaking and there was just this rumbling sound. It was a bad quake

Danny Sharma, a manager at Rodeway Inn in Gilroy

There were no immediate reports of serious damage or injuries, though local media reports say some telephone lines were down.

According to the United States Geological Survey, the earthquake probably took place along the infamous San Andreas Fault and was followed by four smaller aftershocks.

Reports say the tremor was felt throughout the San Francisco Bay area.

Danny Sharma, a manager at Rodeway Inn in Gilroy, said the motel shook violently.

"It was the worst one I've ever felt. The whole building was shaking and there was just this rumbling sound. It was a bad quake," Mr Sharma told the Associated Press.

Games go on

But the earthquake did not stop the National Hockey League play-off in San Jose between the Colorado Avalanche and the San Jose Sharks.

Some people at the game did not even notice that anything had happened.

"I looked around, I said something wrong is going on here. Everything was shaking," said Michel Goulet, an official with the Colorado Avalanche.

"You start thinking, should I run or what? I wasn't sure what to do."

But players on both teams said they knew nothing about an earthquake until they came off the ice and were told.

"I didn't feel anything. This building is pretty loud, so it's shaking anyway," said Colorado's Milan Hejduk.