Ett fingeravtryck hittades på brottsplatsen.

Because fingeravtryck is an ett-word in Swedish, also called a neuter noun.

So:

• ett fingeravtryck = a fingerprint
• fingeravtrycket = the fingerprint

In Swedish, you have to learn whether a noun takes en or ett.

It is a compound noun:

• finger = finger
• avtryck = imprint, print, or mark

So fingeravtryck literally means something like finger print/impression, which matches the English word fingerprint very closely.

Compound nouns are very common in Swedish, and they are usually written as one word.

The -s marks the passive voice in Swedish.

So:

• hittade = found
• hittades = was found

That means Ett fingeravtryck hittades means A fingerprint was found.

This -s passive is very common in Swedish, especially in formal writing, news, reports, and police-style language.

Because Swedish often forms the passive directly on the verb, instead of using a separate helper verb like English does.

English:

• was found

Swedish:

• hittades

So the meaning of was found is built into the single word hittades.

Swedish can also form passives with bli or vara in some contexts, but here the -s passive is the natural choice.

It is in the past tense.

More specifically:

• hittar = finds / is finding
• hittade = found
• hittades = was found

So the sentence describes something that happened in the past.

på is the preposition used here for location, and brottsplatsen means the crime scene.

The noun is another compound:

• brott = crime
• plats = place
• brottsplats = crime scene
• brottsplatsen = the crime scene

So:

• på brottsplatsen = at the crime scene

Even though på often means on, in Swedish it is also used in many cases where English uses at.

The -en is the definite ending, meaning the.

Compare:

• en brottsplats = a crime scene
• brottsplatsen = the crime scene

In Swedish, the definite article is often attached to the end of the noun instead of being a separate word.

So instead of saying a separate word for the, Swedish often adds an ending:

• -en
• -et
• -na, etc.

This is normal Swedish word order:

• Ett fingeravtryck = subject
• hittades = verb
• på brottsplatsen = place expression

So the structure is basically: Subject + Verb + Place

Even though the sentence is passive, ett fingeravtryck is still the grammatical subject.

You could also change the order for emphasis:

• På brottsplatsen hittades ett fingeravtryck.

That version emphasizes the location first, but the meaning is almost the same.

Because the sentence is talking about a fingerprint, not the fingerprint.

Compare:

• ett fingeravtryck = a fingerprint
• fingeravtrycket = the fingerprint

Using ett makes it indefinite, which is natural when introducing something new in a sentence.

If the fingerprint had already been mentioned before, Swedish might use the definite form instead:

• Fingeravtrycket hittades på brottsplatsen.

Yes, it is very natural, especially in formal or report-like language.

It sounds like something you might read in:

• a police report
• a news article
• a detective novel
• a forensic description

The passive hittades gives it a neutral, factual tone. In everyday speech, people might also say something more active, depending on context, but this sentence is completely normal.

For fingeravtryck:

• singular indefinite: ett fingeravtryck
• singular definite: fingeravtrycket
• plural indefinite: fingeravtryck
• plural definite: fingeravtrycken

This noun has the same form in singular and plural indefinite.

For brottsplats:

• singular indefinite: en brottsplats
• singular definite: brottsplatsen
• plural indefinite: brottsplatser
• plural definite: brottsplatserna

So if there were several fingerprints, you could say:

• Fingeravtryck hittades på brottsplatsen.
• Flera fingeravtryck hittades på brottsplatsen.

It is possible to form passives with bli in Swedish, but hittades is the better and more natural choice here.

Compare:

• Ett fingeravtryck hittades på brottsplatsen. = very natural
• Ett fingeravtryck blev hittat på brottsplatsen. = understandable, but less natural here

The -s passive is especially common in written, factual statements like this one.