At least one San Francisco mugger is using a disturbing strategy to rob Muni passengers then flee: Wait on a Muni Metro platform for a rider to disembark, knock them over and rob them, and hop on the same train their victim was just on as it departs.

That's the technique employed by a robber earlier this week, police said today, when he robbed a 50-year-old woman on a platform for Muni's T-Third line.

It all went down Wednesday at 9:30 a.m., police say, at the Muni stop right behind UCSF's Mission Bay campus at Third Street and Campus Way.

According to the San Francisco Police Department, the victim had just stepped off the T-Third and onto the platform when she saw the suspect running toward her.

The mugger "knocked her down," police say, and while she was flat on the pavement, the suspect "pulled away her wallet that she was holding."

The man then jumped onto the T-Third train his victim had just exited, and made a clean escape with her wallet, cash, and checks, according to the SFPD.

Needless to say, every strategy used by robbers is disturbing, but this seems especially worrisome — the last place you want to be knocked off balance is near an active transit platform, right? It's a good reminder to be especially vigilant when getting off the train, bus, and BART.

Another reason to be vigilant, of course, is that that suspect remains at large. According to the SFPD, no arrests have been made in the case, nor is any additional suspect information available.

Related: Couple Robbed At Gunpoint On Muni Bus