OAKLAND (KCBS) – Bay Area Rapid Transit officials are investigating reports that the lockers of some employees were defaced last month with racist and threatening graffiti.

The group of African American workers have already filed a lawsuit against BART over alleged discrimination and harassment. But on the night of June 27, they said they found racist, threatening graffiti on two of their lockers, and what looked like the beginning of a threatening message on a third locker.

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Attorney Jody LeWitter, who is representing the BART workers, said they reported the graffiti to a supervisor, who notified BART police.

“Our clients took pictures and then basically waited for the police to come,” LeWitter said. “The BART police came but so far, there has been no result from the BART investigation. We’ve been told it’s ongoing, but it has been a month.”

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LeWitter said her clients filed a suit in December, accusing the transit agency of racial harassment and discrimination. She said this latest incident has made them feel unsafe at work.

“They are working nights, with presumably someone who is writing these threats and hanging around,” LeWitter said. “They don’t really feel like BART is coming down on their side enough.”

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BART issued the following statement on Thursday. “BART is taking extremely seriously a report of racist and threatening graffiti found last month on the lockers of three African-American track maintenance workers, General Manager Grace Crunican said today. BART Police were notified within an hour of the time the incident was reported and began an internal investigation that same night, officials said. Police are treating the incident as a hate crime, Crunican said. In addition, BART has hired an independent outside investigator to probe the incident as well as a second outside investigator to do a broader assessment of the morale and relationships among workers in the affected department. BART said an allegation that the workers were ordered to return to work is completely inaccurate. The situation is being addressed according to all legal requirements as well as BART Human Resources protocols and procedures, which include zero tolerance for harassment in the workplace. “