This is the 10998th most frequent Portuguese word.
investigadas
"Investigadas" means "investigated" in English.
Here, 'investigadas' is the past participle used in the passive voice, discussing investigations performed on the subject.
As causas do acidente estão sendo investigadas pelas autoridades.
The causes of the accident are being investigated by the authorities.
In this sentence, 'investigadas' is used as an adjective modifying 'suspeitas,' describing their state of being already investigated.
As suspeitas investigadas até o momento não resultaram em provas.
The suspects investigated so far have not resulted in evidence.
Here, 'investigadas' acts as a past participle adjective describing the meetings which were the subject of investigation.