、。
Among the critics are some who believe the targets imposed on the European Central Bank are inappropriate.
Literal
Criticize people [genitive-の] inside [in-には], European Central Bank [to-に] be-imposed-past target [subject-が] inappropriate is [quotative-と] think people [subject-が] exist.
A measured, editorial-style formulation. The frame ~の中には~がいる/がある ('among X, there are those who Y') is the standard Japanese way to partition a group and isolate a subset — it marks the existence of a particular kind of person within a broader set. 課せられた is the past passive of 課す ('to impose, assess, levy'), modifying 目標 as a relative clause: 'the targets that have been imposed.' The indirect quote ~と考える者 ('people who think that...') uses 者 (もの) rather than 人 to mark a slightly formal, almost legal/analytical tone — 'those who hold this view.'