South Korea is trying to ascertain if there are any South Korean casualties in Wednesday's apparent terrorist attack in the Turkish capital of Ankara that left at least 28 people dead and more than 60 others injured, the Foreign Ministry said Thursday.

The ministry has been contacting Turkish police to gain related information and sent telephone messages to South Korean residents or tourists there, requesting caution.

"We are currently trying to find out if there is any damage to South Korean nationals (from the attack)," a ministry official said on the customary condition of anonymity.

Appearing on a local TV program, Turkish Deputy Prime Minister Numan Kurtulmu? said that the vehicle blast occurred in front of a Turkish air force command near the parliament at around 6:20 p.m. Casualties were mostly military personnel, according to Turkish media.

No terrorist organization has yet claimed responsibility for the attack.

Last month, the Seoul government raised the travel alert level for Istanbul, Turkey, to "restraint" from "caution" following another suicide bombing at a popular mosque in the city. Seoul has four alert levels: travel caution, restraint, recommendation for withdrawal, and travel ban. (Yonhap)