Former Kyrgyz President Kurmanbek Bakiyev has left Kazakhstan, said Kazakh Foreign Ministry spokesman Askar Abdrakhamov on Monday.

"As far as I know, Bakiyev has left the territory of Kazakhstan. We do not know where he is going," said the spokesman as quoted by Russian news agencies.

Bakiyev departed his country late last Thursday and flew to Taraz in neighboring Kazakhstan under the mediation of the United States and Russia, after he fled Bishkek on April 7 amid violent protests in the capital and other cities.

Abdrakhamov, who did not specify the exact time of Bakiyev's departure, confirmed that Bakiyev left Kazakhstan together with his family.

The interim regime said it has received the president's letter of resignation while the ousted leader's family members refuted the authenticity of the letter, saying it was forged.

Meanwhile, the interim government led by former foreign minister Roza Otunbayeva accused the ousted president's brother Zhanysh Bakiyev, also defense minister of the toppled regime, of ordering troops to open fire on protesters on April 7, killing over 80 people.

The interim government also planned to launch an international investigation into the April 7 incidents.