Three NATO’s Resolute Support mission service members from Czech Republic were killed in eastern Afghanistan by a suicide bomber, the U.S. military and Czech authorities said.

In the same attack one American service member and two Afghan soldiers were injured.

They were on foot patrol with Afghan forces, according to NATO sources.

The Czech Republic’s Interior Minister Jan Hamáček issued a statement on his   Twitter microblog, saying, the “Czech Republic has suffered a terrible loss. Our three soldiers were killed in a suicide attack while on a foot patrol with Afghan forces in Parwan province. My thoughts remain with the families and friends of our fallen.”