diff --git a/am-shared/tools-spellcheckers-fstbased-desktop-hfst-dir-include.am b/am-shared/tools-spellcheckers-fstbased-desktop-hfst-dir-include.am
index a3d81aa1..832c704c 100644
--- a/am-shared/tools-spellcheckers-fstbased-desktop-hfst-dir-include.am
+++ b/am-shared/tools-spellcheckers-fstbased-desktop-hfst-dir-include.am
@@ -223,6 +223,7 @@ endif # WANT_SPELLERS
 noinst_DATA+=$(GT_ERRMODELS) \
 			$(INST_FILES)
 
+CLEANFILES=$(ALL_ZHFST_FILES) $(ALL_DESKTOP_ZHFST_FILES)
 ###################################
 ####### HFST build rules: #########
 
diff --git a/am-shared/tools-spellcheckers-fstbased-mobile-hfst-dir-include.am b/am-shared/tools-spellcheckers-fstbased-mobile-hfst-dir-include.am
index 791eec61..3c168479 100644
--- a/am-shared/tools-spellcheckers-fstbased-mobile-hfst-dir-include.am
+++ b/am-shared/tools-spellcheckers-fstbased-mobile-hfst-dir-include.am
@@ -215,6 +215,9 @@ mobilespellerdir=$(datadir)/giella/mobilespellers/
 mobilespeller_DATA=$(MOB_GIELLA_SPELLING_HFST) $(MOB_GIELLA_PREDICT_HFST) \
 				   $(ALT_WS_ZHFST_FILES) $(ALT_ORTH_ZHFST_FILES)
 
+CLEANFILES+=$(MOB_GIELLA_SPELLING_HFST) $(MOB_GIELLA_PREDICT_HFST) \
+			$(ALT_WS_ZHFST_FILES) $(ALT_ORTH_ZHFST_FILES)
+
 endif # WANT_HFST_MOBILE_SPELLER
 endif # CAN_HFST
 endif # WANT_SPELLERS