Soldiers stand guard in front of Notre Dame in Paris, France, Dec. 30, 2015, as France tightened the security ahead of the New Year celebrations. (Xinhua/Li Genxing)

PARIS, June 6 (Xinhua) -- A man armed with a hammer attacked a policeman on Tuesday outside Notre Dame Cathedral in Paris before being shot and wounded, local news channel BFMTV reported.

At 16h30 local time (14h30 GMT), an unidentified man targeted police outside Notre Dame cathedral and threatened them with a hammer. He slightly injured an officer in the head before a second serviceman responded by opening fire, according to the report.

The assailant was injured in his thorax and was hospitalized, it added.

On its tweeter account, Paris police called public to stay away and avoid the zone.

Police had evacuated the square while 900 people remained inside the cathedral, one of Europe's most visited sites, the report added.

Anti-terrorism section of Paris prosecutor office launched an investigation into the incident whose motives remained unknown.