British police have called for vigilance in Britain's churches following an Isis-inspired attack on worshippers in Normandy, France which left an 84-year-old Catholic priest dead and a member of the congregation injured.

At the same time the Home Office has announced a £2.4m ($3.1m, €2.86m) grant to increase security in churches and other places of worship, according to the Guardian. The fund will offer churches, mosques and other religious centres access to floodlights, alarms and CCTV among other security measures.

Neil Basu, the Metropolitan police's deputy assistant commissioner, has said in a statement that security arrangements were being reviewed after the events in northern France and following Islamic State's attacks on other religious groups.

"As we have seen, Daesh and other terrorist groups have targeted Christian as well as Jewish and other faith groups in the West and beyond. Following recent events in France, we are reiterating our protective security advice to Christian places of worship and have circulated specific advice today. We are also taking this opportunity to remind them to review their security arrangements as a precaution," he said.

"While the threat from terrorism remains unchanged at severe we urge the public to be vigilant," Basu added. "Be alert and not alarmed and report any suspicious activity. The UK police service is working tirelessly with our partners to confront the threat and protect all our communities."

French authorities have identified the IS-inspired killer who slit Father Jacques Hamel's throat during morning mass as 19-year-old Adel Kermiche. It has been revealed the teenager was known to authorities at the time of the attack and had been monitored after attempting to travel to Syria.

IS has claimed responsibility for the knife assault, calling Kermiche a soldier, a term the terror group reserves for individuals who carry out atrocities in its name.

Adel Kermiche
The attacker who tried and failed to travel to Syria last year has been identified as 19-year-old Adel Kermiche Facebook