Almost anyone who’s ever hopped behind the wheel of a car probably knows the rage that comes with being stuck behind someone driving too slow, being in front of someone who wants to go too fast, or watching as another driver weaves in and out of lanes, cutting off everyone else in the process.

Some drivers will let such offenses slide, but others get angry, letting their blood pressure rise in conjunction with their middle fingers. People occasionally take it further than a rude gesture. Since last week, there have been four local incidents that escalated into violence.

On Oct. 2 a Walnut man was stabbed in a 7-11 parking lot after becoming engaged in a tailgating dispute that stretched from Walnut to Glendora.

Read more in J.D. Velasco’s story RAGE.

Two days later, another couple of road-rage incidents occurred. The first was in Arcadia and resulted in one man ramming another’s car for tailgating and trying to pass him.

Later that night, a dispute on the 71 Freeway in Chino Hills led to an off-duty police officer shooting two men in a shopping-center parking lot.

And Monday night, a woman was driving in the fast lane of the 210 Freeway through Glendora when she was approached from behind by a car that flashed its highbeams at her, signaling for her to move out of the way. When she refused, the other car sped past her, with its occupants cursing her. Police say a “projectile” of some kind hit the rear window of her car, shattering it.