Problem tenants

Possession - Section 8 and Section 21

I have an agent looking after my houses.
I received a complaint by text direct to my phone about my tenants and asked the agent to warn them. They did warn them.
I now received another text saying that the problems are getting worse and police and anti social teams have been involved. Neither I nor my agent have heard anything about this. I immediately asked my agent to go to the house and serve a section 21. I corresponded back to the complainant and assured them (I do not know who it is who's writing to me) that I have taken steps to start the eviction process but to please speak to the agent to get updated on the progress. Can I get the tenants out any quicker than the notice period for a section 21? Can I go to the courts and ask to force them out sooner?