Labour has suspended one of its most troubled constituency parties after allegations of rule-breaking in the run-up to the next general election, the Guardian can reveal. Leicester East constituency Labour party (CLP), which has been represented by the disgraced parliamentarians Keith Vaz and Claudia Webbe, is the subject of an internal investigation by the party’s headquarters, senior sources have confirmed. Local party officials were expected to choose their next parliamentary party candidate over the next few months but a short candidate list was now expected to be imposed by Labour headquarters instead, sources said. The inquiry follows concerns over Labour’s performance in the city’s local elections in May, when it lost 22 council seats and the Conservatives gained 17, bucking the national trend. The city’s three parliamentary seats were retained by Labour at the last election but in Leicester East the party’s majority fell from 22,428 in 2017 to 6,019 in 2019. In the run-up to the May election, Labour suspended 19 sitting councillors from standing, provoking allegations that black, Asian and minority ethnic candidates had been unfairly targeted. It is understood the party’s decision to suspend the CLP came after it was presented with claims that meetings had been unfairly organised to support a particular faction. A Labour source confirmed the suspension. “The NEC has a duty to safeguard the integrity of CLPs, to ensure that they are properly run in line with the party’s rules and procedures and can operate fully, inclusively and democratically,” the source said. It comes amid claims from senior figures in Leicester that the CLP remains under the influence of Vaz, the former Europe minister who stepped down as a candidate in 2019 after being caught in a tabloid sting offering to acquire cocaine for sex workers. Vaz, who represented the city for 32 years and is honorary president of the CLP, told the Guardian in January that he did not wish to stand again in the seat, and declined to comment on claims that he still controlled his constituency party. Vaz’s allies say that he remains a popular figure among the local community but has always worked within the party’s rules. Webbe, an ally of Jeremy Corbyn, was elected as a Labour MP in 2019 but was suspended by the party after a court ruled that she had harassed another woman. Webbe, who now sits as an independent, maintains her innocence and is appealing against the party ruling. Police descended on the constituency in September after unrest involving large groups of men of south Asian origin. It prompted speculation that Hindu nationalism, known as Hindutva, had been imported from abroad and had fuelled antagonism with local Muslim people – a claim that is contested within the community. In May, after the local elections, Leicester’s mayor, Peter Soulsby, told the BBC he was “deeply troubled” by the extent to which religion was “weaponised” during the campaign. This week, a new political party was launched in Leicester, which plans to offer voters a referendum on the future of the city’s elected mayor role. The former Labour councillor Rita Patel has established One Leicester, which she said would aim to build a “better tomorrow” for the city. Local party officials confirmed they knew about the suspension but Sue Hunter, the chair of Leicester East CLP, said on Wednesday night she had not been made aware. Vaz has been approached for a comment.