Check to make sure you and others are okay. Call the police to document the crash. Take photos of your vehicle and the other vehicles involved. If you cannot get police to the scene, take a video of the other person admitting that they caused the crash and obtain that person's insurance and registration information.
First, attempt to remove your vehicle if it is blocking traffic if you can do so safely. Next, call the police. Their report will contain vital information. Lasly, seek medical care even if you don't think you need it. Some symptoms can present later.
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