An inquest into the deaths of 21 people in the 1974 Birmingham pub bombings will examine whether opportunities were missed to thwart the suspected IRA plot, it has emerged.

More than 44 years after twin blasts ripped through the Mulberry Bush and the Tavern in the Town in Birmingham city centre, the first public investigation of each killing began in a courtroom just streets away.

Jurors were told at the opening hearing they would consider issues including whether a clutch of tip-offs to security services could have help avert tragedy altogether.

Families of the victims have spent decades lobbying for a coroner to unravel the events surrounding November 21 1974, after the original inquests were delayed by the wrongful conviction of six people in 1975.

No-one has ever been held to account for the bloodshed since the acquittal of the so-called Birmingham Six, but the Provisional IRA, a Republican terror group, is widely suspected of bearing responsibility.

Sir Peter Thornton, the coroner, read out the names of the victims to a room packed with bereaved relatives at the Birmingham Civil Justice Centre, before observing a minute’s silence.