Can't kill connections

[Marcin Wisnicki]

I'm trying to kill all connections to/from certain host after reloading 
ruleset to force it to go through new ruleset but it does not seem to work.

My host is a simple gateway with $if_ext being natted to $if_int.

I put this rule as the first filter rule:

  block log quick on $if_ext label "block-ext"

Which should prevent any connection from reaching internet.
State policy is set to if-bound.

Then I kill existing states (tcp and udp):

  pfctl -k $host && pfctl -k 0/0 -k $host
  pfctl -k $gateway && pfctl -k 0/0 $gateway

The states are killed and disappear from pftop but immediately new 
connections get through as if rule "block-ext" didn't exist.

These new states have high rule numbers that correspond to pass rules on 
$if_int.

How is this possible when "block-ext" should block everything ?