Downloading http://mirror.yandex.ru/debian/dists/squeeze-lts/InRelease...

gpgv:  RSA key ID 46925553

Downloading http://mirror.yandex.ru/debian/dists/squeeze-lts/Release...
Downloading http://mirror.yandex.ru/debian/dists/squeeze-lts/Release.gpg...

gpgv:  RSA key ID 46925553

ERROR: unable to fetch mirror: verification of detached signature failed: exit status 2