Three people were killed and more than 20 wounded on Wednesday in an apparent bomb attack on a bus packed with Israeli passengers at a Bulgarian airport, officials said.
The blast occurred on a bus at the Black Sea airport of Burgas which was carrying Israelis, setting off a fire that spread to another two buses, the interior ministry said.
If confirmed to be an attack, it would be the first against Israelis on Bulgarian soil.
"Three people were killed and over 20 injured," an interior ministry press officer told AFP in Sofia, adding that "their nationality is yet to be determined."
Israeli officials told AFP in Jerusalem that Israeli citizens were targeted in an attack at the airport.
Bulgaria's state news agency BTA cited the city's mayor as saying the attack was on Israeli tourists.
"Apparently there was an attack on a bus carrying Israelis at Burgas airport in Bulgaria. A bus carrying Israeli citizens was shot at and an explosive device was thrown," said Ofir Gendelman, a spokesman for Israeli Prime Minister Benjamin Netanyahu,
"What we know is that sometime close to 5:00 pm (1400 GMT) there was a flight that landed in Burgas, the passengers went onto a bus and then there was an explosion that we don't know the source of," said Ilana Stein, deputy spokeswoman for the Israeli foreign ministry.
"What we know is that there are casualties and probably not only injured but also dead. We know that some were Israelis but we don't know if all of them were," she told AFP.
The explosion rocked a bus at a parking lot outside the arrivals terminal at the Black Sea airport shortly after 5:00 pm. Two more buses caught fire but were quickly put out, the Bulgarian interior ministry said.
