OAKLAND (CBS SF) – Minor delays on BART trains in Oakland Friday morning were apparently caused by an unruly passenger talking loudly about weapons of mass destruction, a passenger said on the microblogging website Twitter.

The police activity started at about 9:15 a.m. and was causing delays of about 10 minutes for trains headed into San Francisco, a BART dispatcher said.

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Around the same time, someone named Michelle King posted on Twitter, “on the train to sf; Of the many crazy people, there’s one right now clapping loudly and talking about WOMD,” a reference to weapons of mass destruction.

About five minutes later, King posted, “update – bart police came and got him.”

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The BART dispatcher confirmed that the police activity had ended by about 9:30 a.m., but an agency spokesperson was not immediately available to comment on the incident.

BART has bumped up its number of police patrols on trains following the death of al-Qaida leader Osama bin Laden last weekend, and is encouraging riders to speak up if they notice any unusual behavior, unattended packages or suspicious activity.

Regular train service had resumed through Oakland as of 10:15 a.m., according to BART dispatch.

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