PHILADELPHIA — Bernie Sanders loyalists protested inside and outside the Democratic National Convention site and clashed with police on Tuesday after Hillary Clinton won the party’s presidential nomination.

Despite Sanders’ calls for them to support Clinton, thousands of activists have taken to the streets during the convention this week to voice support for the liberal Vermont U.S. senator and his progressive agenda.

Moments after Clinton became the first woman to be nominated for president by a major U.S. political party, a large group of Sanders delegates and supporters exited the Philadelphia convention site to hold a sit-in inside a media tent. Some had their mouths taped shut. A few spontaneously sang the chorus of the folk song “This Land is Your Land,” and a banner read “we the people.” They said they were holding a peaceful protest to complain about being shut out by the Democratic Party.

“This was not a convention. This was a four-day Hillary party. And we weren’t welcome,” said Liz Maratea, a New Jersey delegate at the media tent protest. “We were treated like lepers.”

In the streets outside, Sanders supporters who had spent the day protesting began facing off with police. Protesters began scaling 8-foot walls blocking off the secure zone around the arena parking lot, and several were detained.