The international community has been paying close attention to Hezbollah, and events in Syria are generating even more concern, particularly in terms of the transfer of weaponry from Syria to Lebanon.

The Bulgarian authorities have not issued a verdict or even an official accusation in the case, but they have said they are pursuing tangible evidence and are investigating the role of Hezbollah. The party should reverse its usual course of refusing to cooperate when faced with such accusations, and pursue a different line, namely come clean.

If the accusations are based on solid ground, Hezbollah officials must explain exactly what happened. They must explain any connection that their party has to the foreign passports found at the scene of the bus bombing in July 2012 that killed five Israeli tourists. Do they condone such attacks?

Prime Minister Najib Mikati has pledged that Lebanon will cooperate with the investigation, which is a praiseworthy step. But he also heads a Cabinet in which Hezbollah is represented, and the party should make clear that it intends to follow the line set down by the head of the government.

It is not in the interest of Hezbollah to hide its head in the sand, and pretend that nothing happened. It is fully aware of the political damage it has incurred by failing to recognize the Special Tribunal for Lebanon, and its refusal to cooperate in any way, shape or form. If Hezbollah is innocent and is confident in its stance, it should prove this openly. But if Hezbollah is somehow involved in the Bulgaria bombing, several key questions emerge.

One is the choice of target. Europe has been in the plus side of the political column for Hezbollah, as it takes a different line than the United States in terms of classifying the party as a terrorist organization. In recent years Hezbollah officials have made periodic visits to European countries, and choosing a EU country as a target can only bring negative consequences.

Also, how does such an attack bring the resolution of the Palestinian issue closer to resolution? Some talk about the attack being a response to the assassination in Damascus of military commander Imad Mughniyeh, but an operation that targets a tour bus is a puzzling one, if this was the motive. Hezbollah touts its military and intelligence capabilities; does it lack the capacity to respond to the Mughniyeh killing by attacking a purely military target? The Canadian and Australian passports found at the site can only invite further anger from these two important Western countries, as if Hezbollah did not have enough to worry about already.

The “old ways” of dealing with serious charges are no longer useful; instead of rhetoric and blanket denial, Hezbollah should offer convincing proof either way.