With no explanation, label each line with "location-GPE", "O", "organization-religion", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
Due
to
its
ties
to
the
Christian
Roman
Empire
,
Persia
's
arch-rival
since
Parthian
times
,
the
Sassanids
were
suspicious
of
Roman
Christianity
,
and
after
the
reign
Constantine
the
Great
sometimes
persecuted
it
.
Due:O
to:O
its:O
ties:O
to:O
the:O
Christian:location-GPE
Roman:location-GPE
Empire:location-GPE
,:O
Persia:location-GPE
's:O
arch-rival:O
since:O
Parthian:O
times:O
,:O
the:O
Sassanids:O
were:O
suspicious:O
of:O
Roman:organization-religion
Christianity:organization-religion
,:O
and:O
after:O
the:O
reign:O
Constantine:O
the:O
Great:O
sometimes:O
persecuted:O
it:O
.:O