A man is behind bars on suspicion of threatening Petaluma firefighters with a knife. The 61-year-old is accused of making “threatening gestures” with the buck knife. The gestures were allegedly directed toward firefighters who were in the middle of a training exercise on Monday. Police say the same man was arrested back in February, on suspicion of brandishing a knife at a man and his eight-year-old daughter at McDowell Elementary School. Police records show he has been arrested 21 times since 2020.