Alaska Airlines, building on its continuing expansion effort in San Diego, announced Tuesday it will add three new nonstop flights and significantly increase flight frequency for four of its more popular routes.

In the latest aviation developments, Alaska Airlines plans to end service this fall on three domestic routes from San Francisco and Los Angeles but will continue to grow at San Diego, adding new routes and more flight frequencies;

Alaska Airlines is launching three new nonstop routes from San Diego later this year, it was announced Tuesday.