One policeman has been killed and two others seriously wounded in a shooting in central Paris, French police sources have said.

The shooting, in which the assailant was also killed, took place on the Champs-Elysees shopping boulevard just days ahead of France's presidential election.

A French interior ministry spokesman said a second policeman had not died of his wounds, as had been earlier reported.

However he confirmed that, apart from the policeman killed on the spot two police officers had been seriously wounded.

"An automatic weapon was used against police, a weapon of war," the spokesman told reporters.

The assailant was known to security services. Police searches are now taking place at his home.

An arrest warrant has been issued for a second suspect who arrived from Belgium by train.

Paris on high alert following shooting of policemen in Paris days ahead of presidential election https://t.co/u84mxoNBd3 pic.twitter.com/oQDD3jeAmQ — RTÉ News (@rtenews) April 20, 2017

A witness told Reuters that a man got out of a car at the scene and began shooting with a machine gun. A police source also said more shots had been fired at another location near the scene.

The self-proclaimed Islamic State has claimed responsibility for the attack, according to the terror group's propaganda agency Amaq.

Outgoing French president Francois Hollande said he is convinced the attack was terrorist related. Mr Hollande will hold a security cabinet meeting tomorrow morning after the attack.

Another interior ministry spokesman said it was too early to say what the motive of the attack was, but it was clear the police officers had been deliberately targeted.

The French prosecutors' office said the counter-terrorism office had opened an inquiry.

However three police sources said that the shooting could have been an attempt at an armed robbery.

Police authorities called on the public to avoid the area.

TV footage showed the Arc de Triomphe monument and top half of the Champs Elysees packed with police vans, lights flashing and heavily armed police shutting the area down after what was described by one journalist as a major exchange of fire near a Marks and Spencer store.

The incident came as French voters prepared go to the polls on Sunday in the most tightly-contested presidential election in living memory.

A number of the leading candidates in that election, including Marine Le Pen and Francois Fillon, have cancelled campaign events tomorrow due to the shooting.

France has lived under a state of emergency since 2015 and has suffered a spate of Islamist militant attacks that have killed more than 230 people in the past two years.

Earlier this week, two men were arrested in Marseille whom police said had been planning an attack ahead of the election.

A machine gun, two hand guns and three kilos of TATP explosive were among the weapons found at a flat in the southern city along with jihadist propaganda materials according to the Paris prosecutor.