Thousands of motorcycles rolled down the streets of the nation's capital Sunday in a rally organized by Rolling Thunder (search), a biker group that supports veterans' rights.

The group has been staging the rally on Memorial Day (search) weekend since 1988 to focus attention on POW-MIA issues.

Many of the bikers took part in the annual memorial ride from Arlington National Cemetery (search) to the National Vietnam War Memorial before heading to the Lincoln Memorial.

The Chairman of the Joint Chiefs of Staff, Gen. Richard Myers (search), and his wife joined the thousands of bikers riding through Washington.

Later in the day, Defense Secretary Donald H. Rumsfeld (search) gave a speech to members of Rolling Thunder near the Lincoln Memorial. He thanked the veterans' commitment to the cause of freedom.