In Harry Potter and the Order of the Phoenix, Dumbledore uses a spell to knock out the ministry wizards in his office in order to escape.
A streak of silver light flashed around the room. There was a bang like a gunshot, and the floor trembled. A hand grabbed the scruff of Harry's neck and forced him down on the floor as a second silver flash went off - several of the portraits yelled, Fawkes screeched, and a cloud of dust filled the air. Coughing in the dust, Harry saw a dark figure fall to the ground with a crash in front of him. "No!" The sound of breaking glass, frantically scuffling footsteps, a groan - and silence.
Harry Potter and the Order of the Phoenix. Chapter 27, The Centaur and the Sneak
When the smoke clears it's revealed the ministry folks have been knocked out and Dumbledore says they won't remember anything.
The descriptions of the incident don't make sense to me. What's with the "no!" and frantically scuffling footsteps? Who made those sounds? I doubt the footsteps belonged to Dumbledore (he's anything but frantic), and they wouldn't belong to McGonagall or the kids as they were on the floor. As for the "no!", it doesn't make sense for Dumbledore/ McGonagall/ Marietta to say it.
I always got the impression they were made by the ministry wizards, but then why would they still be conscious after the spell ended? What knocked them out? What were they doing?