Choose the sentence with the correct usage of nouns:
1
Police has been searching for the absconding thief's whereabouts for a long time.
2
Police are searching for the absconding thief's whereabouts for a long time.
3
Police is searching for the absconding thief's whereabouts for a long time.
4
Police have been searching for the absconding thief's whereabouts for a long time.