It’s been disturbing to learn of the bombs at the Boston Marathon. Some have expressed surprise that a sports event was attacked and others have wondered if it could happen at the Tour de France.

But it has happened before. As the video clip above from 1974 shows, several vehicles were destroyed by plastic explosives planted by GARI, a political group that was active at the time.

In 1987 French police intercepted Basque separatists armed with weapons, explosives and incendiary devices along with a map of the Pyrenees on which the route of one of the Tour stages was highlighted in blue and police believed the race was going to be attacked.

As recently as 2007 two small devices exploded on 25 July on the route of the Tour de France but nobody was harmed.

GARI has vanished and the Basque group ETA has announced a “definitive ceasefire”.

High profile contests and large crowds attract attention, usually for all the right reasons but sadly for negative ones too. The Tour remains a celebration and nobody should be scared to take part in the fun.