"The Koran, two telephones were found ... and the instrument of the crime - a knife measuring 30 centimeters with a blade 17 centimeters long," Le Monde quoted him as saying.
Ricard also clarified that two more knives were found in the church.
Earlier it was reported that the attack in Nice was carried out by a native of Tunisia.
On October 29, three people were killed in an attack on parishioners in a church in central Nice.
According to the mayor of the city, Christian Estrosi, the crime was committed by a "radicalized Muslim".
French President Emmanuel Macron called the incident a terrorist attack.