WATCH: Bernie Sanders' supporters hold sit-in protest in media tent

PHILADELPHIA, Pennsylvania (WABC) -- Moments after Hillary Clinton officially won the Democratic nomination for president, a large group of Bernie Sanders' supporters left the convention hall in Philadelphia to hold a sit-in protest at a nearby tent for journalists.

WATCH: Sade Baderinwa was live in the media tent during the sit-in protest:

Some supporters had their mouths taped shut. A few others sang "This Land is Your Land" and held a banner that read, "We The People."

They say they're holding a peaceful protest to complain about being shut out by the Democratic Party.

One protester is 64-year-old Talat Khan, of San Bernardino, California.

He says: "It's for the betterment of our children and the future of our children."

In the midst of the sit-in protest, one woman silently celebrated Hillary Clinton's historical nomination.

Earlier Tuesday, Sanders asked the convention to nominate Clinton by acclamation. The delegates did so, to wild cheers inside the Wells Fargo Center.

(Some information from the Associated Press)