PRAGUE (AP) — The Czech Republic has announced that it is expelling 18 Russian diplomats identified as spies over a huge ammunition depot explosion in 2014.

Prime Minister Andrej Babis said Saturday that the Czech intelligence agencies provided clear evidence about the involvement of Russian military agents in the massive explosion that killed two people.

Babis said the Czech Republic is a sovereign state and must react to those findings.

Interior Minister Jan Hamacek, who is also serving as the foreign minister, said those 18 Russian embassy staffers were clearly identified as Russian military spies and were ordered to leave the country within 48 hours.