Amazon.com on Tuesday unveiled the first of a dozen Volvo electric big rigs it plans to deploy this year to pick up cargo from the nation's busiest container seaport in Southern California.

Amazon is deploying 50 battery-electric heavy-duty trucks in California, which it claims is the largest such fleet in the country. The company says the new trucks represent an important step in its mission to eliminate pollution from its global operations — even as its carbon emissions have spiked in recent years.

The e-commerce giant said it already has eight of those semi trucks in use at the Los Angeles/Long Beach port complex, where every so-called drayage truck must be zero-emissions by 2035