diff --git a/src/mod/applications/mod_lcr/mod_lcr.c b/src/mod/applications/mod_lcr/mod_lcr.c
index 3fd06d96a5..700446f03e 100644
--- a/src/mod/applications/mod_lcr/mod_lcr.c
+++ b/src/mod/applications/mod_lcr/mod_lcr.c
@@ -691,11 +691,12 @@ static switch_status_t is_intrastatelata(callback_t *cb_struct)
 	   e164 format without the +
 	   NANP only (so 11 digits starting with 1)
 	 */
-	if (!cb_struct->lookup_number || (strlen(cb_struct->lookup_number) != 11 && *cb_struct->lookup_number != '1')) {
+	if (!cb_struct->lookup_number || (strlen(cb_struct->lookup_number) != 11 && *cb_struct->lookup_number != '1') || 
+		!switch_is_number(cb_struct->lookup_number)) {
 		/* dest doesn't appear to be NANP number */
 		return SWITCH_STATUS_GENERR;
 	}
-	if (!cb_struct->cid || (strlen(cb_struct->cid) != 11 && *cb_struct->cid != '1')) {
+	if (!cb_struct->cid || (strlen(cb_struct->cid) != 11 && *cb_struct->cid != '1') || !switch_is_number(cb_struct->cid)) {
 		/* cid not NANP */
 		return SWITCH_STATUS_GENERR;
 	}