The Plague or Pestilence was Attributed to a Destroying Angel
Source: TTT
Exodus 12:23
When the LORD passes through to strike down the Egyptians, He will see the blood on the top and sides of the doorframe and will pass over that doorway; so He will not allow the destroyer to enter your houses and strike you down.
2 Samuel 24:16
But when the angel stretched out his hand to destroy Jerusalem, the LORD relented from the calamity and said to the angel who was destroying the people, “Enough! Withdraw your hand now!” At that time the angel of the LORD was by the threshing floor of Araunah the Jebusite.