Deep State War? Russian Officials Keep Dying Unexpectedly

Six Russian diplomats have died in the last 60 days. As Axios notes, all but one died on foreign soil. Some were shot, while other causes of death are unknown. Note that a few deaths have been labeled "heart attacks" or "brief illnesses." Are we witnessing a battle between the deep state and Russia in a spy versus spy plotline or is this all just a freak coincidence?