(JTA) — Palestinian officials apologized for a cache of illegal weapons discovered at the home of the Palestinian ambassador to the Czech Republic a day after he was killed in an explosion there.

The Czech Foreign Ministry said in a statement issued Tuesday that the Palestinians apologized for the weapons, which were not registered with Czech authorities, and promised to prevent such occurrences in the future, The Associated Press reported.

Jamal Al-Jamal, who in October was named the Palestinian envoy to Prague, was killed Jan. 1 when a safe in the home exploded. Conflicting reports said the safe had not been in use in 20 years or that it had been in regular use.

The safe had been moved recently from a former embassy building that had housed the offices of the Palestinian Liberation Organization more than two decades ago. The ambassador reportedly removed some of the safe’s contents before it exploded, according to AP.

Czech police do not suspect foul play.