Iraqi security forces clashed with anti-government demonstrators in Baghdad on Sunday with at least 39 people, most of them police officers, injured by projectiles unleashed from each side, security officials said.

Police sources said tear gas canisters being fired by security forces had injured at least seven people.

A separate statement from a military spokesman said at least 32 members of the security forces were injured by hand grenades thrown by a group he suggested had hidden among otherwise peaceful protesters, without elaborating.

Politicians have expressed concern at the possibility of peaceful protests being hijacked by rioters, which could set off a spiral of violence such as that witnessed last year.