Did you pick them off the host
plant? and hard to see them in the photo... too bright and too far away. They could be cutworms. What are they feeling on? are they eating the
flowers? or the leaves? Need more info to help you out.
But they do look like a type of caterpillar (cutworms are a kind of caterpillar), hard to count legs from the photos. The other option could be a sawfly (type of wasp larva) but again have to count legs.
more info please
but to kill them you could pick them off or if they are caterpillars you could spray Bt.