A bus at the Burgas airport in Bulgaria exploded in what is being characterized early as a terrorist attack on Israelis tourists. Dimitar Nikoliv, the Mayor of Burgas confirmed the event on the radio. According to an Israeli witness, the bus was shuttling Israeli passengers between terminals, Haaretz is now reporting that there are several dead and wounded.

Update, 12:10 PM:
Haaretz is reporting that at least seven people were killed in the attack, 20 more wounded.

Initial report: Israeli tour bus blown up at Bulgaria airport [Ynet]
Explosion in bus with Israeli passengers [Focus]
Several killed, wounded in terror attack against Israelis in Bulgaria [Haaretz]