Charlie Kirk’s suspected assassin may have been working with others, the head of the FBI has suggested.

Kash Patel told a congressional committee that the bureau was investigating several people who communicated with Tyler Robinson, who last week was accused of shooting Kirk, through an online messaging platform.

Mr Patel, who has faced criticism over his handling of the case, was questioned by Congress over the 31-year-old influencer’s assassination at a university event in Utah.

“There are a number of individuals that are currently being investigated and interrogated, and a number yet to be investigated and interrogated, specific to that chat room,” Mr Patel told the Senate judiciary committee on Tuesday.

Asked by a senator whether others could have been involved, he answered: “Yes sir.” Mr Patel was referring to a Discord chatroom Mr Robinson was involved with, in which he is said to have posted a message admitting to the killing.