Policeman
Noun
けいさつかん
警察官が容疑者を発見した際、男は丘の上で美しい風景画を描いていました。
When the police officer found the suspect, he was painting a beautiful landscape on a hilltop.
The police (警察) government is full of police officers. This is the formal way to say "police officer." It is similar to 警官, but has a slightly more official feel to it.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.