SAN DIEGO -- Animal rights activists spoke out Saturday night against the way elephants are being kept at the San Diego Zoo, 10News reported.

Protestors greeted people going to the zoo's black-tie fundraiser.

The demonstators are upset over the zoo's plan to expand its elephant exhibit.

The expansion project would bring the exhibit space up to 2 acres in land area. It is currently less than 1 acre.

Animal rights activists said the proposed expansion is still not enough.

A zoo spokesman said it could take a couple of years before the expansion is complete.