SAN FRANCISCO (CBS SF) — Three people wearing ski masks robbed San Francisco’s Wells Fargo History Museum early Tuesday morning, police said.

The robbery took place at about 2:30 a.m. at 420 Montgomery St., near California Street when suspects drove a blue Chevrolet Suburban SUV into the museum and plowed through a display case, according to police.

The thieves drove through two 1" doors made of laminated glass. Estimated repair cost: $150-200K. #sfgoldheist pic.twitter.com/x0pbqKEp6q — Ryan Takeo (@ryantakeo) January 27, 2015

They held up the security guard at gunpoint and stole between four to ten ounces in gold nuggets. The guard was not hurt.

The robbers left the scene in light-colored Ford Taurus.

The estimate of damages is not yet known. The museum building was once occupied by the first Wells Fargo branch office in San Francisco.

This gold nugget on the counter made it through the heist. Just chilling on the Wells Fargo counter. pic.twitter.com/jc9rKjIHZT — Ryan Takeo (@ryantakeo) January 27, 2015

Wells Fargo spokesman Ruben Pulido said the company is grateful that no one was hurt and that the museum’s historic stagecoaches went undamaged during the robbery.

Paulido said the company is cooperating with the police department’s investigation and that the museum will reopen so it can serve the thousands of people that visit each year.

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