Charlie Hebdo massacre: New police killing rocks Paris
A gunman has killed a policewoman in Paris, a day after suspected Islamists killed 12 people at the office of a satirical magazine, the BBC reported.
A second person was seriously injured in the attack in the southern suburb of Montrouge, after which the gunman fled.
It is unclear of the incident is related to the Charlie Hebdo massacre, which traumatised France.
Police have made seven arrests in the hunt for two brothers, the main suspects,. A third has surrendered.
Arrest warrants were issued for Cherif and Said Kouachi, said to be "armed and dangerous."
Sources close to the investigation told AFP news agency of a report that the two had been spotted on Thursday in a car on a road in the Aisne region of northern France.
They were reportedly recognised by the manager of a service station near the town of Villers-Cotteret, and still armed.
A minute's silence was observed at midday (11:00 GMT) across the country as France observed national mourning for the victims of the Charlie Hebdo attack. The bells of Notre Dame cathedral in the capital tolled in mourning.