diff --git a/src/controllers/notifications_controller.rs b/src/controllers/notifications_controller.rs
index d61d0f0..cfe656e 100644
--- a/src/controllers/notifications_controller.rs
+++ b/src/controllers/notifications_controller.rs
@@ -58,6 +58,19 @@ pub fn mark_seen(r: &mut HttpRequestHandler) -> RequestResult {
     let notif_id = r.post_notif_id("notifID")?;
     let delete_similar = r.post_bool_opt("delete_similar", false);
 
-    // TODO : continue implementation
-    r.success("continue implementation")
+    // Check if we are targeting a precise notification or an undetermined number of similar
+    // notifications
+    if !delete_similar {
+        notifications_helper::delete(
+            &PartialNotification::new()
+            .set_id(notif_id)
+        )?;
+    }
+
+    else {
+        // TODO : implement me
+        unimplemented!();
+    }
+
+    r.success("Notification deleted")
 }
\ No newline at end of file
diff --git a/src/data/notification.rs b/src/data/notification.rs
index 1c8064a..0e334cd 100644
--- a/src/data/notification.rs
+++ b/src/data/notification.rs
@@ -189,6 +189,10 @@ impl PartialNotification {
         self
     }
 
+    pub fn has_id(&self) -> bool {
+        self.id.is_some()
+    }
+
     pub fn set_dest_user_id(mut self, id: &UserID) -> PartialNotification {
         self.dest_user_id = Some(id.clone());
         self
diff --git a/src/helpers/database.rs b/src/helpers/database.rs
index 3d1be84..6a9787f 100644
--- a/src/helpers/database.rs
+++ b/src/helpers/database.rs
@@ -660,6 +660,12 @@ impl DeleteQuery {
         }
     }
 
+    /// Add batch conditions
+    pub fn add_conditions(mut self, conditions: HashMap<String, mysql::Value>) -> Self {
+        self.conditions.extend(conditions.into_iter());
+        self
+    }
+
     /// Add a string condition
     pub fn cond_str(mut self, key: &str, value: &str) -> DeleteQuery {
         self.conditions.insert(key.to_string(), Value::from(value));
diff --git a/src/helpers/notifications_helper.rs b/src/helpers/notifications_helper.rs
index 8842b0d..bc7c52d 100644
--- a/src/helpers/notifications_helper.rs
+++ b/src/helpers/notifications_helper.rs
@@ -10,7 +10,31 @@ use crate::data::notification::{NotifElemType, NotifEventType, NotifEventVisibil
 use crate::data::user::UserID;
 use crate::helpers::database;
 
-/// check out whether a similar notification exists for given specifications
+/// Delete notifications
+pub fn delete(notification: &PartialNotification) -> ResultBoxError {
+
+    // Check if we have to delete a specific notification or a group of similar notifications
+    let conditions = match notification.id {
+        Some(id) => {
+            let mut map = HashMap::new();
+            map.insert("id".to_string(), mysql::Value::from(id));
+            map
+        }
+
+        // Delete similar notifications
+        None => {
+            notif_to_db(notification, false)
+        }
+    };
+
+
+    // Delete the notifications
+    database::DeleteQuery::new(NOTIFICATIONS_TABLE)
+        .add_conditions(conditions)
+        .exec()
+}
+
+/// Check out whether a similar notification exists for given specifications
 pub fn similar_exists(n: &PartialNotification) -> ResultBoxError<bool> {
     database::QueryInfo::new(NOTIFICATIONS_TABLE)
         .add_conditions(&notif_to_db(n, false))