French candidates boost security ahead of tense vote

France's presidential candidates have been blanketing the country with campaign events amid increased security to try to inspire undecided voters just four days before a nail-biting election.

Crowds danced on a Paris plaza as Socialist presidential candidate Benoit Hamon held what was seen as a last-chance rally and concert.

Mr Hamon is polling in a distant fifth place ahead of Sunday's first-round election and has little chance of reaching the decisive May 7 run-off - a failure that could crush his party.