It appears that knife crimes have been the order of the last day or so, with four suspects at large after incidents that left victims injured and/or robbed.

Among those crimes are two stabbings, according to the San Francisco Police Department. In one case, reported at 9:55 a.m. Tuesday at the intersection of Stevenson Street and Duboce Avenue, a 33-year-old man was stabbed with an "unknown thin metal object" by a male acquaintance aged 35-40.

The victim was transported to San Francisco General Hospital for injuries not considered life-threatening, police say. The suspect fled on foot in an unknown direction.

A second stabbing occurred at 4:47 Wednesday morning at 14th and Mission Streets, an intersection very close to Tuesday's crime. In that case, police say callers reported a fight in the street, and when they arrived they discovered a male victim who'd been stabbed in the leg.

Police say that the victim's injuries are life-threatening, and he was transported to SF General for care. The other combatant fled, according to the SFPD.

Less serious, but still disturbing, are two knifepoint robberies reported Tuesday. In the first, which took place at 6 a.m., a 33-year-old man standing at the corner of Larkin Street and Golden Gate Avenue was threatened at knifepoint by a suspect aged around 20-26 over what police say was "an unpaid debt."

After grabbing the victim by the arm and brandishing his blade, the suspect took the victim's backpack "and walked away," according to the SFPD.

Then at 6:22 p.m., a 25-year-old woman was robbed at knifepoint on the 2600 block of Mission Street, which is between 22nd and 23rd Streets.

According to the SFPD, the unknown male suspect produced a knife "and brandished it toward [the victim]," then "fled on bike with stolen clothing."

Police say that in all these cases, no arrests have been made. If you know anything about any of these (or other) crimes, please call the SFPD's anonymous tip line at 415-575-4444, or text a tip to TIP411 and begin the text message with SFPD.

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