The identity of the second man involved in the killing of a priest in northern France on Tuesday has been revealed as Abdel Malik Petitjean, aged 19.

Petitjean, from eastern France had been on the French terror watch list. Police said they had been looking for him for several days before the attack.

"Following DNA tests, it emerged that the terrorist has been identified as Abdel Malik Nabil Petitjean," a source in the Paris prosecutor's office told French media.

The other attacker has been identified as Adel Kermiche, also 19.

The pair were shot dead by police after they entered a small Catholic church in Saint-Etienne-du-Rouvray, near Rouen in northern France and slit the throat of the priest, Father Jacques Hamel, as he celebrated mass. They took the five congregation members hostage, critically injuring one, before being "neutralised" by French police.

The names of the attackers were confirmed after it emerged a mosque in Saint-Etienne-du-Rouvray was opened on land donated by the church.

Mohammed Karabila, imam of the mosque in Saint-Etienne-du-Rouvray, said the two religious communities had close relations in the small suberb. He added that he sat on an interfaith committee with Father Hamel.

The gesture, made in 2000, of land for the mosque appears to be emblematic of the strong ties between the two religious communities.

Karabila said he was "stunned" by Hamel's death, whom he described as a close friend.

"I don't understand, all of our prayers go to his family and the Catholic community," said Karabila, as quoted by German news site Deutsche-Welle. "He was someone who gave his life to others. We are dumbfounded at the mosque.

"We talked about religion and how to live together. It has been 18 months that civilians have been attacked; now they are attacking religious symbols, using our religion as a pretext. It is no longer possible," he said.