diff --git a/src/controllers/ConversationsController.ts b/src/controllers/ConversationsController.ts
index 41379e9..cf1723f 100644
--- a/src/controllers/ConversationsController.ts
+++ b/src/controllers/ConversationsController.ts
@@ -132,7 +132,7 @@ export class ConversationsController {
 
 		// Check for new conversations
 		if(h.hasPostParameter("newConversations")) {
-			for(const convID of h.postNumbersSet("newConversations")) {
+			for(const convID of h.postNumbersSet("newConversations", 0)) {
 				if(!ConversationsHelper.DoesUsersBelongsTo(h.getUserId(), convID))
 					h.error(401, "You are not allowed to fetch the messages of this conversation ("+convID+")!");
 				
@@ -144,7 +144,37 @@ export class ConversationsController {
 			}
 		}
 
-		// TODO : Check for refresh on some conversations
+		// Check for refresh on some conversations
+		if(h.hasPostParameter("toRefresh")) {
+			const toRefresh = h.postJSON("toRefresh");
+
+			for (const key in toRefresh) {
+				if (toRefresh.hasOwnProperty(key)) {
+					const element = toRefresh[key];
+					
+					// Extract conversation ID
+					if(!key.startsWith("conversation-"))
+						h.error(400, "Entries of 'toRefresh' should start with 'conversation-' !");
+					const convID = Number.parseInt(key.replace("conversation-", ""));
+
+					// Extract last message ID
+					if(!element.hasOwnProperty("last_message_id"))
+						h.error(400, "Missing last_message_id for conversation " + convID + "!");
+					const lastMessageID = Number.parseInt(element.last_message_id);
+
+					// Check user rights
+					if(!ConversationsHelper.DoesUsersBelongsTo(h.getUserId(), convID))
+						h.error(401, "You are not allowed to fetch the messages of this conversation ("+convID+")!");
+					
+					// Get the messages
+					list["conversation-" + convID] = (await ConversationsHelper.GetNewMessages(convID, lastMessageID))
+						.map(e => this.ConversationMessageToAPI(e));
+
+					// Mark the user has seen the messages
+					await ConversationsHelper.MarkUserSeen(convID, h.getUserId());
+				}
+			}
+		}
 
 		h.send(list);
 	}
diff --git a/src/entities/RequestHandler.ts b/src/entities/RequestHandler.ts
index 66769d4..1752a44 100644
--- a/src/entities/RequestHandler.ts
+++ b/src/entities/RequestHandler.ts
@@ -103,9 +103,10 @@ export class RequestHandler {
 	 * Get a list of integeres included in the request
 	 * 
 	 * @param name The name of the post field
+	 * @param minEntries Specify the minimum number of entries required
 	 */
-	public postNumbersList(name: string) : Array<number> {
-		const param = this.postString(name);
+	public postNumbersList(name: string,  minEntries : number = 1) : Array<number> {
+		const param = this.postString(name, minEntries < 1 ? 0 : minEntries, minEntries > 0);
 		let list = [];
 		for (const el of param.split(",")) {
 			
@@ -119,6 +120,9 @@ export class RequestHandler {
 			
 		}
 
+		if(list.length < minEntries)
+			this.error(400, "Not enough entries in '" + name + "'!")
+
 		return list;
 	}
 
@@ -126,9 +130,29 @@ export class RequestHandler {
 	 * Turn a list of string into a Set object
 	 * 
 	 * @param name Name of POST field
+	 * @param minEntries Minimum number of entries to specify
 	 */
-	public postNumbersSet(name : string) : Set<number> {
-		return new Set(this.postNumbersList(name));
+	public postNumbersSet(name : string, minEntries : number = 1) : Set<number> {
+		return new Set(this.postNumbersList(name, minEntries));
+	}
+
+	/**
+	 * Attempt to decode JSON included in a POST request
+	 * 
+	 * @param name Name of POST field
+	 */
+	public postJSON(name: string) : any {
+		const src = this.getPostParam(name);
+
+		if(src == undefined)
+			this.error(400, "Missing JSON '" + name + "' in the request!");
+		
+		try {
+			const response = JSON.parse(src);
+			return response;
+		} catch(e) {
+			this.error(500, "'" + name + "' is not a valid JSON !");
+		}
 	}
 
 	/**
diff --git a/src/helpers/ConversationsHelper.ts b/src/helpers/ConversationsHelper.ts
index 1d19cde..f4f12d8 100644
--- a/src/helpers/ConversationsHelper.ts
+++ b/src/helpers/ConversationsHelper.ts
@@ -255,6 +255,24 @@ export class ConversationsHelper {
 			},
 			limit: numberOfMessages,
 			order: "id DESC"
+		})).map(m => this.DBToConversationMessage(convID, m)).reverse();
+	}
+
+	/**
+	 * Get the new messages of a conversation
+	 * 
+	 * @param convID Target conversation ID
+	 * @param lastMessageID The ID of the last known message
+	 */
+	public static async GetNewMessages(convID: number, lastMessageID: number): Promise<Array<ConversationMessage>> {
+		return (await DatabaseHelper.Query({
+			table: MESSAGES_TABLE,
+			where: {
+				conv_id: convID
+			},
+			customWhere: "ID > ?",
+			customWhereArgs: [lastMessageID.toString()],
+			order: "id"
 		})).map(m => this.DBToConversationMessage(convID, m));
 	}