It is a police officers obligation to find out why someone runs from them. There is a reason he ran; had he just committed a crime; was he hiding drugs; did he have outstanding warrants? If he did nothing, he would have been questioned and let go.
The knife issue came after they captured him. If the knife was not legal (we don’t have the facts yet)that is probable cause. No reason to condemn the officers at this point.
Law enforcement or Crime Prevention. Which one do you prefer?