diff --git a/src/flags.js b/src/flags.js
index b93902fa63..be8ba8856f 100644
--- a/src/flags.js
+++ b/src/flags.js
@@ -469,7 +469,10 @@ Flags.purge = async function (flagIds) {
 	const userFlags = flagData.filter(flagObj => flagObj.type === 'user');
 	const assignedFlags = flagData.filter(flagObj => !!flagObj.assignee);
 
-	const allReports = await db.getSortedSetsMembers(flagData.map(flagObj => `flag:${flagObj.flagId}:reports`));
+	const [allReports, postCids] = await Promise.all([
+		db.getSortedSetsMembers(flagData.map(flagObj => `flag:${flagObj.flagId}:reports`)),
+		posts.getCidsByPids(postFlags.map(flagObj => flagObj.targetId)),
+	]);
 	const allReporterUids = allReports.map(flagReports => flagReports.map(report => report && report.split(';')[0]));
 	const removeReporters = [];
 	flagData.forEach((flagObj, i) => {
@@ -485,7 +488,7 @@ Flags.purge = async function (flagIds) {
 			...flagData.map(flagObj => ([`flags:byType:${flagObj.type}`, flagObj.flagId])),
 			...flagData.map(flagObj => ([`flags:byState:${flagObj.state}`, flagObj.flagId])),
 			...removeReporters,
-			...postFlags.map(flagObj => ([`flags:byCid:${flagObj.targetCid}`, flagObj.flagId])),
+			...postFlags.map((flagObj, i) => ([`flags:byCid:${postCids[i]}`, flagObj.flagId])),
 			...postFlags.map(flagObj => ([`flags:byPid:${flagObj.targetId}`, flagObj.flagId])),
 			...assignedFlags.map(flagObj => ([`flags:byAssignee:${flagObj.assignee}`, flagObj.flagId])),
 			...userFlags.map(flagObj => ([`flags:byTargetUid:${flagObj.targetUid}`, flagObj.flagId])),