Security warning: Where should I look for?

[Antonio Rodriguez <arodriguez31@cfl.rr.com>]

I just received a strong warning:

tony@hpd:~$ scp p173* root@remote.ip.here:/pathto/
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
24:40:94:e0:81:b9:af:62:dd:70:84:47:10:d1:c3:c0.
Please contact your system administrator.
Add correct host key in /home/tony/.ssh/known_hosts to get rid of this message.
Offending key in /home/tony/.ssh/known_hosts:2
RSA host key for local.ip.here has changed and you have requested strict checking.
Host key verification failed.
lost connection
tony@hpd:~$ 

Thanks to all.