diff --git a/src/news_gui.cpp b/src/news_gui.cpp
--- a/src/news_gui.cpp
+++ b/src/news_gui.cpp
@@ -761,6 +761,31 @@ CommandCost CmdCustomNewsItem(TileIndex 
 		default: return CMD_ERROR;
 	}
 
+	const WindowDesc *desc = _news_subtype_data[subtype].desc;
+	for (int i = 0; i < desc->nwid_length; i++) {
+		if (desc->nwid_parts[i].type == NWID_VIEWPORT && reftype1 != NR_VEHICLE && GetReferenceTile(reftype1, p2) == INVALID_TILE) {
+			return CMD_ERROR;
+		}
+	}
+
+	switch (subtype) {
+		/* These sub types require more parameters that are never passed. */
+		case NS_COMPANY_TROUBLE:
+		case NS_COMPANY_MERGER:
+		case NS_COMPANY_BANKRUPT:
+		case NS_COMPANY_NEW:
+			return CMD_ERROR;
+
+		/* This one only accepts engines. */
+		case NS_NEW_VEHICLES:
+			if (reftype1 != NR_ENGINE) return CMD_ERROR;
+			break;
+
+		/* The rest, in theory, accepts everything. */
+		default:
+			break;
+	}
+
 	if (company != INVALID_OWNER && company != _local_company) return CommandCost();
 
 	if (flags & DC_EXEC) {
diff --git a/src/script/api/script_news.hpp b/src/script/api/script_news.hpp
--- a/src/script/api/script_news.hpp
+++ b/src/script/api/script_news.hpp
@@ -22,26 +22,11 @@
 class ScriptNews : public ScriptObject {
 public:
 	/**
-	 * Enumeration for corners of tiles.
+	 * Enumeration for the news types that a script can create news for.
 	 */
 	enum NewsType {
 		/* Note: these values represent part of the in-game NewsSubtype enum */
-		NT_ARRIVAL_COMPANY   = ::NS_ARRIVAL_COMPANY,  ///< Category arrival for own company.
-		NT_ARRIVAL_OTHER     = ::NS_ARRIVAL_OTHER,    ///< Category arrival for other companies.
-		NT_ACCIDENT          = ::NS_ACCIDENT,         ///< Category accident.
-		NT_COMPANY_TROUBLE   = ::NS_COMPANY_TROUBLE,  ///< Category company in trouble.
-		NT_COMPANY_MERGER    = ::NS_COMPANY_MERGER,   ///< Category company merger.
-		NT_COMPANY_BANKRUPT  = ::NS_COMPANY_BANKRUPT, ///< Category company bankrupt.
-		NT_COMPANY_NEW       = ::NS_COMPANY_NEW,      ///< Category company new.
-		NT_INDUSTRY_OPEN     = ::NS_INDUSTRY_OPEN,    ///< Category industry open.
-		NT_INDUSTRY_CLOSE    = ::NS_INDUSTRY_CLOSE,   ///< Category industry close.
 		NT_ECONOMY           = ::NS_ECONOMY,          ///< Category economy.
-		NT_INDUSTRY_COMPANY  = ::NS_INDUSTRY_COMPANY, ///< Category industry changes for own company.
-		NT_INDUSTRY_OTHER    = ::NS_INDUSTRY_OTHER,   ///< Category industry changes for other companies.
-		NT_INDUSTRY_NOBODY   = ::NS_INDUSTRY_NOBODY,  ///< Category industry changes for nobody.
-		NT_ADVICE            = ::NS_ADVICE,           ///< Category advice.
-		NT_NEW_VEHICLES      = ::NS_NEW_VEHICLES,     ///< Category new vehicle.
-		NT_ACCEPTANCE        = ::NS_ACCEPTANCE,       ///< Category acceptance changes.
 		NT_SUBSIDIES         = ::NS_SUBSIDIES,        ///< Category subsidies.
 		NT_GENERAL           = ::NS_GENERAL,          ///< Category general.
 	};