KIEV, Sept. 8 - President Viktor Yushchenko accepted the resignation of Oleksandr Turchynov, the chief of Ukraine's security service, or SBU, Thursday hours after dismissing the government of Prime Minister Yulia Tymoshenko.

Turchynov, a close ally of Tymoshenko, warned Yushchenko that the dismissal of the government ???jeopardizes the national security of Ukraine," but had never spelled out the nature of the threat.