CAMBRIDGE – Cambridge police removed four people who identified themselves as members of Black Lives Matter/Cambridge from the front door of City Hall, where they had chained themselves early Wednesday.

Two protesters, both women, used U-shaped bike locks to connect themselves to the door handles of the building around 6 a.m. The women were also linked to two other protestors, both men, with plastic tubing wrapped in red duct tape.

Police cleared the protesters around 9:30 a.m. by removing the door handles. Police then slid a tarp-like material underneath the demonstrators and pulled them away from the entryway.

Police surrounded the protestors — the women remained locked together — in the corner near the entryway.

Officers have blocked supporters’ attempts to provide water to the people who are locked together. Police went as far as to pull a bottle out of one person’s hand.

However, officials have provided water of their own to protesters to keep them hydrated.

On social media, the demonstrators say they are members of Black Lives Matter/Cambridge who are protesting the lack of affordable housing in the city.

About three dozen people gathered in front of City Hall Wednesday morning, chanting, “The people united will never be defeated,” and, “Brick by brick, wall by wall, racist systems have to fall.’’

Cambridge police spokesman Jeremy Warnick said City Hall employees are using other entrances to get to work, and that no arrests have been made. Police will stay at the rally until it ends.

“Obviously, everything is orderly and everything is peaceful,” he said.

The protesters have been using the Periscope streaming video application to broadcast from the scene. Four police officers were blocking the front steps at one point.

City Councilor Marc McGovern addressed the crowd with a megaphone. At times, his remarks were rebuffed by protesters, and the interaction seemed tense.

McGovern said he would not sign a pledge committing to the group’s list of demands, but said the issue of affordable housing is important.

“It’s a delicate balance,” he said. “But I just want you to know that this is important to us, and we’ve been on this for a while.”

He said the issue of affordable housing “occupies a majority of our time,” as officials seek ways for families to stay in the town.

The protest group wants city leaders to support and enact four proposals:

• Require developers with more than nine units to make 25 percent of the development affordable housing.

• Allow MIT to build dorms for 5,500 graduate and postgraduate students, increasing housing availability for city residents.

• Use city-owned properties to develop affordable housing.

• Create a “rent to own” program in the city.

One person at the event who said she was a member of the protest movement, said she believes the town is struggling to meet its affordable housing goals as the city’s housing market grows more expensive.

“Meanwhile, the people of color are disappearing. Meanwhile, Cambridge is getting less and less affordable for average people. Meanwhile, families are disappearing,” she said. ‘We’re here because we’re saying we want to keep Cambridge Cambridge.”

Globe correspondent Dylan McGuinness and John R. Ellement of the Globe staff contributed to this report. Steve Annear can be reached at steve.annear@globe.com. Follow him on Twitter @steveannear.