Labour leadership candidate Ed Miliband has been criticised for hiring an anti-Israel researcher to work on his campaign, despite the volunteer having previously been sacked by another MP.

Joseph Brown, a former anti-racism officer at London School of Economics’ student union, is working on Mr Miliband’s website during the leadership contest.

While at LSE, Mr Brown allegedly made comments about having “shot down a Zionist” during an anti-Israel lecture theatre occupation in the wake of Operation Cast Lead.

He also proposed an anti-Israel motion which drew complaints from fellow students and was pictured at a Free Palestine protest wearing a traditional Arab keffiyeh head-dress and declaring his “continued dedication to the Palestinian cause”.

In a profile explaining his role with Mr Miliband, Mr Brown wrote: “I have travelled the country with Ed and his campaign team, filming and editing videos and working in his volunteers’ office and phone banks.

“Everything we do as volunteers is not just appreciated, but actively valued by the team, which reflects the style of Ed’s inclusive leadership.”

Mr Miliband’s team said it was unaware of Mr Brown’s earlier anti-Zionist comments and sacking by Brent North MP Barry Gardiner. The former Energy Secretary, son of Jewish Marxist thinker Ralph Miliband, is running against his older brother David, the former Foreign Secretary.

A spokesman for Mr Miliband said: “Looking at these reported comments, they are clearly reprehensible, and we completely reject them. The campaign has benefited from hundreds of enthusiastic volunteers, who undertake a variety of tasks.

“The person in question is an unpaid volunteer and has clearly already paid a price for this silly behaviour in the past. We understand that he lost a previous job as a result of the comments he reportedly made while still a student.”

The Union of Jewish Students said: “We are disappointed to hear that Ed Miliband has failed to dissociate himself from an individual who, throughout his time as anti-racism officer at LSE, showed little regard for minority students. We urge the Miliband campaign to reconsider its position.”

Mr Gardiner, former vice-chair of Labour Friends of Israel, sacked Mr Brown from a similar campaigns role last year after he failed to reveal his previous views during his job interview.

But the MP said he supported Mr Miliband’s decision to stand by the volunteer. “It would be a great shame if every time Seph wanted to do something constructive for the Labour movement he was met with an outcry over his previous views.”