Twitter has been told to “look again” for evidence of Russian interference in UK politics as new research appears to show the social network under-reported the problem to MPs.

Data unearthed by the Press Association shows more than 2,400 tweets about the UK, Brexit, the refugee crisis and last year’s general election came from at least 154 accounts linked to the Internet Research Agency (IRA), a Kremlin-linked organisation accused of sowing disinformation on social media.

Many of the accounts had tens of thousands of followers, with some messages shared thousands of times between 2015 and 2017, but the full scale and impact of the campaign is currently unclear because of the limited data available.

Twitter told MPs on a parliamentary committee investigating fake news in February that it had found 49 such accounts tweeting specifically about Brexit, after months of pressure from its chairman Damian Collins.

But Twitter’s evidence fell short of the demand Mr Collins has requested in letters since November that the company provides “a list of accounts linked to the Internet Research Agency and any other Russian linked accounts that it has removed and examples of any posts from these accounts that are linked to the United Kingdom”.

Mr Collins told the Press Association: “There’s clearly been a lot more activity than they acknowledged. So does that mean they were unaware of it or that they just aren’t looking for it?”

He said he would be asking the social media network to look once more for evidence of Russian interference in UK politics on its platform in light of the research.

“It confirms the view that Twitter cannot be allowed to mark its own homework,” said Ian Lucas, who also sits on the Department for Culture, Media and Sport select committee. “It seems an extraordinary state of affairs that such influential businesses can ask for everything to be taken on trust.”

A Twitter spokesman stressed that the shortfall had occurred because the company’s investigation had focused on the Brexit campaign specifically, not the 2017 election or other issues around UK politics.

All of the 154 accounts found to have been involved were “permanently suspended” last autumn, it added.

He added: “Our CEO Jack Dorsey has detailed our new ‘Health’ initiative and opened up a request for proposals to external parties to come and inform our path forward. We don’t claim to have all the answers.”

The accounts, identified by cross-referencing Twitter’s own list of IRA-linked accounts with databases of millions of tweets gathered by researchers in the UK and US, were particularly active around terrorist attacks or political events, and could be found celebrating the Brexit result and amplifying anti-European or Islamophobic messages.

Many of the tweets painted the refugee crisis across Europe as a Muslim invasion, stirring up anti-Muslim and anti-immigration sentiment.

Others falsely described some crimes, such as incidents in Munich and London’s Russell Square, as terrorist attacks.

Anti-European and anti-immigration tweets were included in the final dataset because immigration regularly featured at the top of polls for reasons given by voters wanting to leave the European Union.

One account with thousands of followers, @pamela_moore13, tweeted regularly about Muslims and crimes committed by “refugees” across Europe.

“Muslims in Britain complain that #GeneralElection2017 will be held during Ramadan,” read one @pamela_moore13 tweet. “I think it’s a great idea!”

One tweet from the account decrying a French “muslim no-go zone” was the most shared in the data.

“France is lost,” reads the tweet, accompanied by a video. “#French police try to enter a muslim no-go zone. We can not allow this in America!”

Although the tweet is now deleted, many copies exist sent by other accounts. The video shows clashes between police and rioters during the 2014 Sarcelles riots in Paris. It was retweeted more than 6,000 times.

A tweet from a known Russian troll account stirs up anti-Muslim sentimentThis tweet from known Russian troll @Pamela_Moore13 was shared thousands of times

Elsewhere, multiple accounts tweeted about #ReasonsToLeaveEu on the day of the Brexit vote, and one, @foundingson, sent a string of tweets as the UK government triggered Article 50, beginning the official process of leaving the European Union.

“Historic day!” read one such tweet. “Congratulations, Britain! You’re independent! #Brexit #Aticle50[sic]”

Thousands more targeted the US election and US politics as well as French and German elections.

An EU official who tracks Russian information campaigns on social media said the aim of the Internet Research Agency is to “weaken the west… from the top level to the lowest level”.

“They are looking for divisive topics,” said the official, who did not wanted to be identified.

“In many countries it will be the migration crisis as it will polarise the audience and make them more hysterical. So they won’t listen to facts but instead listen to emotions.”

The tweets sent by IRA-linked accounts about the UK were not all malicious or partisan in nature, however, neither were they all original. The accounts run from St Petersburg would often retweet news organisations, politicians or prominent figures discussing the issues of the day.

In February, the IRA and 13 Russian individuals were charged with conspiracy to defraud the United States for their alleged meddling in the 2016 US election.

While the United States has named oligarch Yevgeny Prigozhin, a senior ally to Russian President Vladimir Putin, as the organisation’s lead funder, the Kremlin has denied any involvement.

The true number of Russian accounts targeting British politics has the potential to be far higher than this new research shows, because of the partial way in which the data was collected and the restrictions on accessing data once Twitter removes it.

Twitter does, however, allow access to more data about activity on its platform than some of its rivals. As a result, relatively little independent research has been conducted into how IRA employees used Facebook, YouTube, Reddit and the comment threads of news websites.

Academics have proposed collaboration between social networks, governments and universities to preserve data of historical significance, rather than deleting it when it is discovered.

“Without any external access to this data, there is no ability to independently audit the scale of the problem, to understand how and when users have interacted with disinformation, and to understand how disinformation moves across platforms,” wrote Claire Wardle, a research fellow at Harvard’s Shorenstein Media Center, in written evidence to the parliament’s fake news inquiry.

“Even if they stop accounts being active they should keep a record of the account to help researchers see what’s going on,” agreed Mr Collins.

The inquiry will meet again on Wednesday to question Matt Hancock, secretary of state for digital, culture, media and sport, on the Government’s response to online disinformation campaigns from foreign actors.

A Government spokesman said: “To date, we have not seen evidence of successful interference in UK democratic processes by a foreign government.”