Two people died and five others were treated in hospital for injuries after a rally car drove into a crowd watching the event near Bailieborough, Co. Cavan, on Sunday.

The tragic accident blighted the warmest day for several years in Ireland and the event, known as the Cavan Stages Rally, was promptly halted.

Caroline Cleary, one of the two who died, was 14 weeks pregnant with her first child. The 29-year-old from Co. Wexford had just moved to a better spot to watch her boyfriend Sean Hayde in a car in which he was navigator and co-driver when another car struck her.

Cleary was an experienced rally navigator and co-driver with Wexford Motor Club who remained out of Sunday’s event because of her pregnancy.

Motorsports photographer Joe Lane, 50, from Kilcolgan, Co. Galway, who was standing near her, was also killed as the two were mowed down by a Ford Escort rally car which went out of control after going over a bump.  It ploughed into 30 spectators.

More than 100 cars competed in the event, which attracted thousands of spectators.

Both the Gardai (police) and Motorsport Ireland, which governs the sport, begun separate investigations, including inquiring into whether the spectators killed and injured and those put at risk, were standing in a designated area.  It’s understood the group were asked to move back a number of times.

Areas which are unsafe for spectators are clearly marked out with signs.

Eyewitness Mathew McMahon described the scene. He said, “I heard people screaming, ‘Red flag, red flag, stop the stage.’ Then all hell broke loose, basically. There were people crying; people white as ghosts. It was clear something serious had happened.”

Pat O'Dowd, of Wexford Motor Club, said the sport was Cleary's life. He added, “Caroline always had a smile on her face and was always happy to help. Motor sport was her life.”

The tragedy follows others which have devastated the sport in Ireland in recent years.

Teenage rally fan Richard O'Donnell, from Strabane, was killed as he tried to cross a country road during the Donegal International Rally in 2008.

The 18-year-old was struck by a competing Ford Fiesta on the eleventh stage of the competition, which is one of the biggest sporting events in the country.

Two years ago co-driver Thomas Maguire died in a crash in the Donegal rally, and in 2002 two stewards were also killed in the event.