A group of Russian deputies has announced a hunger strike in protest against a new law on state benefits that has sparked a wave of rallies.

The Rodina faction's five MPs said they would refuse food and remain inside parliament until the law replacing social benefits with cash is scrapped.

Ministers responsible for the reform, meanwhile, admitted serious mistakes in its implementation at a heated session.

Thousands of pensioners protested again as the lower house - or Duma - met.

The Rodina faction walked out of the Duma session devoted to the reform which replaces benefits - such as free transport and subsidised medicine for pensioners and invalids - with cash compensation.

We, naturally, tend to say ' a group of people have protested against ..........

In the above, you will read the words ' a group of Russian deputies has announced a hunger strike in protest against ..........

Is it correct?
in my humble idea, the usage is correct.

such nouns are called collective nouns and there are specific rules for their usages.

1- if the group performs an action together---has
2- if we talk about the size of the group ---has
3- if the group disagree on sth ---have
4- if the members of the group perform an action individually -not for a common target ---have

in your sentence, #1 applies.

When you disagree, it should be have whereas when you agree it should be has. I find it very hard to accept.
Are you able to refer me to a book to look at this point?
Students: We have free audio pronunciation exercises.
see Michael Swan "practical english usage" chapter:503
Would you tell me the year which the book was printed? My book of Swan doesn't have the same page.
it is 1997. not page but chapter 5003Emotion: smile

besides, I have other sources printed in Turkish, one of which is the most popular reference books in Turkey -ELS English Grammar Inside and Out.
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