Given the task definition and input, reply with output. This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Passage: Russian ( , russkiy yazyk, pronounced [ruskj jzk] ( listen)) is an East Slavic language and an official language in Russia, Belarus, Kazakhstan, Kyrgyzstan and many minor or unrecognised territories. It is an unofficial but widely-spoken language in Ukraine, Latvia, Estonia, and to a lesser extent, the other countries that were once constituent republics of the Soviet Union and former participants of the Eastern Bloc. Russian belongs to the family of Indo-European languages and is one of the three living members of the East Slavic languages. Written examples of Old East Slavonic are attested from the 10th century onwards. Question: When was the earliest writing in Old East Slavonic?
10th century