Boston Public Library trustees voted Friday to close four branches, including the one in Lower Mills.

But City Councillors At-Large Felix Arroyo and Ayanna Pressley, and West Roxbury's Councillor John Tobin vowed to fight to keep all the branches open when the city council gets the proposed budget next week.

"Today is not the end," Arroyo said. "We will do everything we can to ensure this nightmare does not become real."

Tobin, whose mother made him write reports on books he took out of the Lower Mills branch, agreed. "We're talking about the very fabric of our city - kids and families. We do that we might as well go home. What else do we have?"

Trustees voted 5-0 to shut the four branches. Trustee Paul LaCamera abstained after other trustees rejected his proposal to keep the Orient Heights branch in East Boston open.

For more on the Trustees' vote today- and reaction- see this report from Neighborhood Network News:

Library Trustees Vote to Close Branches from Chris Lovett on Vimeo.

State Rep. Linda Dorcena-Forry said she and other Boston legislators are working to try to get additional funding for the BPL at the state level. But she said the city has to do its part as well; the state let the city increase the hotel tax and BPL officials and workers should be exploring measures such as furlough days.

In a statement, Mayor Thomas Menino called the vote "difficult but necessary." "This is a challenging budget year which requires tough decisions and I am confident that 22 strong branches will help secure the long term financial security and services of our libraries," he said. "I plan to accept the board’s branch closure recommendations and the City will soon announce plans for the East Boston, Brighton, Dorchester and South Boston neighborhoods affected by these closures so that residents can continue to access library services in their communities.”

But Claire Hughes of the Lower Mills Civic Association noted the Lower Mills branch is not as close to some institutions as the other closed branches - the doomed Oak Square branch is across the street from a YMCA - and said she did not understand why the relatively modern branch should be shut.

Supporters of the Lower Mills branch are holding a fundraiser at the Ledge restaurant on Wednesday from 6 p.m. to 8 p.m.

“The battle is going to continue,” said Tony Paciulli, president and CEO of Meetinghouse Bank, who helped gather over 4,000 signatures from residents asking trustees to keep the library open.

He added: “I’ve had all kinds of people coming in today. Voicemails, emails. The bottom line is this: the fundraiser is going to go on.”

Paciulli noted that city councillors have the power to veto the budget. "Now the pressure is really on the elected officials to make their positions clear," he said. "There’s no neutrality here. There’s no middle position."

Meanwhile, trustee Chairman Jeffrey Rudman would not commit to re-opening branches if the BPL did come up with the $3.6 million officials say they need to close a budget gap, promising only to reconvene trustees to determine the best way to spend such a hypothetical amount.

Trustee Paul LaCamera said he despaired of getting any additional funds when he saw only three city councilors and just one state legislator at today's meeting.

Asked by the Reporter whether she would vote for a budget that includes library closures, Pressley said, "I hope I'm not going to have to make that decision."

"If this happens, this stands to destabilize neighborhoods," she said after leaving the meeting. "This is an incredibly sobering moment."

Arroyo said voting on a budget with closures would be "very difficult." "It's important to allow the mayor to make his case," he added.

City Councillor Maureen Feeney, whose district includes the Lower Mills branch and three others, said supporters of the library "deserve every ounce of support."

She has caught some flack from some library supporters for not signing onto an April 2 letter nine councillors sent to BPL President Amy Ryan and trustees. The letter called on trustees to conduct a thorough review of BPL finances and said closing libraries should be a "last resort."

Feeney, who has also been enmeshed in a family health matter, said councillors have to vet the budget first before making promises about what not to chop.

"I can yes people to death...but I've tried in my 16 years [on the council] to be honest," Feeney said. "We don't know what else is in the budget."

"What we don't know is how deep the cuts are to every department," she said. "I just think we have to work through this process."

She added: "Why Lower Mills? These are the kinds of questions we'll be asking."

Councillors are due to be briefed on the Menino administration's fiscal 2011 budget at 8 a.m. Wednesday at City Hall.