Here’s the title rewritten in Swedish:

”Minst fyra dödade i rysk drönarattack mot Cherson, uppger tjänstemän”

A few notes on the translation choices:

• ”At least four killed” → ”Minst fyra dödade” — this is the standard Swedish news phrasing for casualty reports.
• ”Russian drone attack” → ”rysk drönarattack” — direct equivalent, with ”rysk” in the indefinite singular form as is customary in Swedish headlines.
• ”on Kherson” → ”mot Cherson” — the city is typically rendered Cherson in Swedish (the Swedish transliteration from Cyrillic), and mot conveys the sense of an attack directed at the city.
• ”officials say” → ”uppger tjänstemän” — this is a standard Swedish journalistic formula, though enligt tjänstemän (”according to officials”) would also work. Note that tjänstemän can mean both ”officials” and ”civil servants”; if the officials in question are government spokespeople rather than civil servants, enligt myndigheterna (”according to the authorities”) could be an alternative.

If you’d like a slightly more compact headline (Swedish news headlines often drop the verb är), you could also write:

”Minst fyra dödade i rysk drönarattack mot Cherson”

This version omits the attribution entirely, which is common in Swedish headlines when the source is implied.