Israel: Bomb explodes on railway track

Four people have been injured after a bomb exploded on a railway line near the central Israeli city of Lod.

It had been planted on the train tracks and detonated as a train passed by, according to the head of Israel's train system Yossi Snir.

Palestinian militants have stepped up attacks on Israel's public transport system, killing scores of people in suicide bombings, since an uprising began 21-months-ago.

But it was the first time a bomb was reported to have exploded on train tracks.

The injured were travelling on a crowded train passing on a nearby track.

"We were very lucky," national police spokesman Gil Kleiman said, alluding to the relatively low number of casualties, adding that police were treating it as "a terrorist attack".

The bomb detonated as the train packed with 500 people went by a parallel track during the morning rush hour at the start of the Israeli work week.

Several of the train's windows were shattered, Israel's national railway authority said. Kleiman said the bomb contained five kilograms of explosives and shrapnel.