Russian tech giant Yandex says it has been exposed in a cyber security incident.

MOSCOW, Jan 31, 2010 (FBC) – Russian technology company Yandex ( YNDX.O ) said on Tuesday that fragments of its program’s code were leaked online, and a preliminary investigation revealed a violation of some of its internal policies.

“The company is taking the matter seriously and has launched a thorough investigation into the cause, content and implications of the leak,” Yandex’s Dutch holding company said in a statement.

It found no evidence of users’ personal data being affected, but said the number contained the addresses of some of its partners.

“Most of these and other issues that emerged following the code leak have been fixed or are in the process of being fixed,” he said.

Since Russia sent its armed forces into Ukraine last February, the websites of several Russian companies and news sites have been subject to sporadic hacking attempts.

Data released in March exposed the personal information of more than 58,000 people on Yandex’s food delivery app Yandex.Eda.

Reuters report; Writing by Caleb Davis; Edited by Christina Fincher

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