Use WMI (Windows Management Instrumentation).

This book has 2 pages on WMI details, and 4 sample programs:
Win32 Perl Scripting: The Administrator's Handbook

This book has 7 pages on WMI details, and 4 code snippets:
Perl for System Administration: Managing multi-platform environments with Perl

A WMI tutorial, SDK, and documentation are available for download from Microsoft.

Working skeleton code, derived (and bug-fixed) from both books:

#!/usr/bin/perl -W
# WMI_for_monks.pl
use warnings 'all';
use strict;
use Win32::OLE('in');

my ($Machine, $pid_to_kill) = @ARGV;
$Machine =~ s{^[\\/]{2,}}{};

my $CLASS = 'WinMgmts:{impersonationLevel=impersonate}!//'
          . $Machine;

my $WMI = Win32::OLE->GetObject( $CLASS )
   or die Win32::OLE->LastError();

foreach my $proc (in $WMI->InstancesOf('Win32_Process')){
    next unless $proc->{ProcessId} == $pid_to_kill;
    printf "Killing:%7d\t%s\n",
           $proc->{ProcessId}, $proc->{Name};
    $proc->Terminate(0);
}
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This command:
WMI_for_monks.pl COSMOS 952
produced this output:
Killing:    952 winbff32.exe