March 24 (UPI) -- Sen. Bernie Sanders called on Americans to "stand up to hatred of all kinds" during a visit to a Los Angeles Islamic center a week after a shooting at two New Zealand mosques left 50 people dead.

The Democratic presidential candidate from Vermont spoke at the Islamic Center of Southern California on Saturday before holding a rally for thousands of supporters in the city's Grand Park.

"In this difficult moment, not only in American history where we see a rise in hate crimes, and not only in a world where we see a growing tendency toward authoritarianism, where demagogues are picking on minority communities all over this world, now is the time ... for us to stand up to hatred of all kinds," Sanders told about 200 people gathered at the Islamic center.

He said as president he would be a leader who brings all people together regardless of religion.

"Your background is different than mine," Sanders aid. "What a joy it is to share that."

An Australian man opened fire March 15 at two New Zealand mosques, an attack officials there called a terror plot motivated by extremism. The suspected gunman posted anti-Muslim remarks online before the shooting, police said.

At his later appearance Saturday, Sanders drew a crowd of about 12,000 people, a Los Angeles Fire Department official told the Los Angeles Times.

He again spoke against xenophobia and the fossil fuel industry, and in favor of social, racial, economic and environmental justice.

"At a moment in history where we are seeing a huge explosion in technology, and huge increases in worker productivity, we will no longer accept a situation in which the younger generation will have a lower standard of living than their parents," Sanders said.

He called for elections to be paid for by public funds so that "anyone running for office can do so without depending on billionaires."

Sanders was scheduled to hold a third California event Sunday in San Francisco.