Arsenal are investigating a series of antisemitic social media posts from an account allegedly belonging to a member of their staff.

Mark Bonnick, a kitman at the north London club’s academy, is understood to be facing an internal inquiry after posts on an account on X featuring his name and photograph were shown to have a number of exchanges with members of the Jewish community. The account was changed to ­protected status on Wednesday afternoon and appeared to have been deleted on Wednesday night.

The exchanges have taken place over the past month and were highlighted by @Never_Again2020, an account focused on tackling antisemitism.

On 24 November Bonnick apparently posted to David ­Collier, an investigative journalist and ­prominent antisemitism campaigner, in relation to Israel’s war with Hamas in Gaza: “Yes it is all about Jewish supremacy & not wanting to share the land Ethnic cleansing.” Another alleged post to Collier on 4 December suggested that “Zionist Israel” had a “persecution complex”.

On 1 December Bonnick’s alleged post to Heidi Bachram, a campaigner against antisemitism, said: “Because you didn’t scream when Zionist Israel refused their release Hamas refused to release all hostages in October … You abandoned them … Refused to bring them home … Your silence was deafening … Now you want others to scream … Morals integrity honesty none … Mark of Cain.”

A further alleged post to other users said: “Why should they be protected anymore than any other community? Some see this as the problem Jewish communities thinking they should be put before others.” On 29 November the account allegedly asked other users: “What about the Jews that attack Christians?”

An Arsenal spokesperson said: “We are investigating this matter in line with our internal policies and ­procedures. Arsenal stands against all forms of abuse and discrimination.”

The Guardian was unable to reach Bonnick for comment and to ­confirm that he owned the account. If the posts were shown to have been posted by Bonnick he could face an investigation by the Football ­Association, which has been alerted to the matter.