Update, 1 p.m.:

The Boston-area transit agency's fiscal control board has approved a contract that will privatize the agency's cash collecting and counting operations.

The board approved the five-year $18.7 million contract with Virginia-based Brink's on Thursday with a 4-0 vote, with one member absent.

The privatization effort was opposed by unions representing Massachusetts Bay Transportation Authority workers. They say privatizing the so-called money room in the city's Charlestown neighborhood would cost dozens of jobs.

T officials say outsourcing the operation will save millions of dollars per year.

Seven members of Carmen's Union Local 589 were arrested Thursday while picketing outside the money room. They face arraignment in Charlestown Municipal Court on unlawful assembly charges. They're accused of trying to prevent armored cars from entering or exiting the facility.

10:15 a.m.:

A spokeswoman for the Carmen's Union says the members of the Local 589 executive committee were arrested Thursday morning and charged with unlawful assembly and disorderly conduct.

About 100 picketers assembled outside the Massachusetts Bay Transportation Authority's so-called "money room" to prevent workers and armored cars from entering.

The MBTA plans to recommend to its fiscal control board on Thursday that Virginia-based Brink's be awarded a five-year, $18.7 million contract to oversee the Charlestown facility.

An outside review found widespread security issues at the facility that collects and counts an estimated $119 million in cash annually.

The Carmen's Union, which represents more than 4,100 MBTA workers, opposes outsourcing.